Impact modification of thermoplastics with ethylene/alpha-olefin interpolymers

ABSTRACT

Compositions having good impact performance can be made from a thermoplastic (e.g., a polyolefin such as polypropylene or HDPE) and an ethylene multi-block copolymer. The compositions are easily molded and often have particular utility in making, for example, automotive facia, parts and other household articles.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to PCT Application No.PCT/US2005/008917 (Dow 63558D), filed on Mar. 17, 2005, which in turnclaims priority to U.S. Provisional Application No. 60/553,906, filedMar. 17, 2004. The application further claims priority to U.S.Provisional Application Ser. No. 60/717,928 filed Sep. 16, 2005 (Dow64495). For purposes of United States patent practice, the contents ofthe provisional applications and the PCT application are hereinincorporated by reference in their entirety.

FIELD OF THE INVENTION

This invention relates to improved impact modification of thermoplasticpolymers and polymer blends.

BACKGROUND AND SUMMARY OF THE INVENTION

Many different polymers and materials have been added to polymercompositions in attempting to enhance the composition's impact strengthor maintain the impact strength while enhancing other properties. Forexample, U.S. Pat. No. 5,118,753 (Hikasa et al.), incorporated herein byreference, discloses thermoplastic elastomer compositions said to havelow hardness and excellent flexibility and mechanical propertiesconsisting essentially of a mixture of an oil-extended olefiniccopolymer rubber and an olefinic plastic. The olefinic plastic ispolypropylene or a copolymer of polypropylene and an .alpha.-olefin of 2or more carbon atoms. Modern Plastics Encyclopedia/89, mid October 1988Issue, Volume 65, Number 11, pp. 110-117, the disclosure of which isincorporated herein by reference, also discusses the use of variousthermoplastic elastomers (TPEs) useful for impact modification. Theseinclude: elastomeric alloys TPEs, engineering TPEs, olefinic TPEs (alsoknown as thermoplastic olefins or TPOs), polyurethane TPEs and styrenicTPEs.

Thermoplastic olefins (TPOs) are often produced from blends of anelastomeric material such as ethylene/propylene rubber (EPM) orethylene/propylene diene monomer terpolymer (EPDM) and a more rigidmaterial such as isotactic polypropylene. Other materials or componentscan be added into the formulation depending upon the application,including oil, fillers, and cross-linking agents. TPOs are oftencharacterized by a balance of stiffness (modulus) and low temperatureimpact, good chemical resistance and broad use temperatures. Because offeatures such as these, TPOs are used in many applications, includingautomotive facia and wire and cable operations, rigid packaging, moldedarticles, instrument panels, and the like.

Union Carbide Chemicals and Plastics Inc. announced in 1990 that theyhave developed a new cost effective class of polyolefins trademarkedFlexomer™ Polyolefins that could replace expensive EPM or EPDM rubbers.These new polyolefins are said to have bridged the gap between rubbersand polyethylene, having moduli between the two ranges. Modulus of therubber and of the formulation is not, however, the only criteria forevaluating a TPO formulation. Low temperature impact performance,sometimes measured by Gardner Impact at −30° C. also is sometimesimportant to a TPO composition's performance. According to the datacontained in FIG. 4 of the paper “Flexomer™ Polyolefins: A BridgeBetween Polyethylene and Rubbers” by M. R. Rifi, H. K. Ficker and M. A.Corwin, more of the Flexomer™ Polyolefin needs to be added into the TPOformulation in order to reach the same levels of low temperature GardnerImpact performance as the standard EPM rubber, thus somewhat negatingthe benefits of the lower cost EPM/EPDM replacement. For example, usingthe data of FIG. 4 of the Rifi et al paper, about 20% (by weight) of theEPM in polypropylene gives a Gardner Impact of about 22 J. at−30.degree. C., while the same amount of Flexomer™ Polyolefin gives a−30° C. Gardner Impact of about 13 J.

In a paper presented on Sep. 24, 1991 at the 1991 Specialty PolyolefinsConference (SPO '91) (pp. 43-55) in Houston, Tex., Michael P. Jeffries(Exxpol Ethylene Polymers Venture Manager of Exxon Chemical Company)also reports that Exxon's Exact™ polymers and Plastomers can be blendedinto polypropylene for impact modification. Exxon Chemical Company, inthe Preprints of Polyolefins VII International Conference, page 45-66,Feb. 24-27 1991, also disclose that the narrow molecular weightdistribution (NMWD) resins produced by their EXXPOL™ technology havehigher melt viscosity and lower melt strength than conventional Zieglerresins at the same melt index. In another recent publication, ExxonChemical Company has also taught that NMWD polymers made using a singlesite catalyst create the potential for melt fracture (“New SpecialtyLinear Polymers (SLP) For Power Cables,” by Monica Hendewerk andLawrence Spenadel, presented at IEEE meeting in Dallas, Tex., September,1991).

It is well known that narrow molecular weight distribution linearpolymers disadvantageously have low shear sensitivity or low I₁₀/I₂value, which limits the extrudability of such polymers. Additionally,such polymers possessed low melt elasticity, causing problems in meltfabrication such as film forming processes or blow molding processes(e.g., sustaining a bubble in the blown film process, or sag in the blowmolding process etc.). Finally, such resins also experienced surfacemelt fracture properties at relatively low extrusion rates therebyprocessing unacceptably and causing surface irregularities in thefinished product.

Thus, while the development of new lower modulus polymers such asFlexomer™ Polyolefins by Union Carbide or Exact™ polymers by Exxon hasaided the TPO marketplace, there continues to be a need for other moreadvanced, cost-effective polymers for compounding with thermoplastics(e.g., polyolefins such as polypropylene or HDPE) to improve or maintainmodulus and/or impact performance at room temperature or below.

Formulated compositions have now been discovered to have thiscombination of good low temperature impact performance and modulus. Thecompositions comprise:

A) a thermoplastic selected from the group consisting of thermoplasticpolyurethanes, polyvinyl chlorides, styrenics, engineeringthermoplastics, and polyolefins, and

B) an impact-modifying amount of at least one ethylene/α-olefininterpolymer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the melting point/density relationship for the inventivepolymers (represented by diamonds) as compared to traditional randomcopolymers (represented by circles) and Ziegler-Natta copolymers(represented by triangles).

FIG. 2 shows plots of delta DSC-CRYSTAF as a function of DSC MeltEnthalpy for various polymers. The diamonds represent randomethylene/octene copolymers; the squares represent polymer examples 1-4;the triangles represent polymer examples 5-9; and the circles representpolymer examples 10-19. The “X” symbols represent polymer examplesA*-F*.

FIG. 3 shows the effect of density on elastic recovery for unorientedfilms made from inventive interpolymers (represented by the squares andcircles) and traditional copolymers (represented by the triangles whichare various Dow AFFINITY® polymers). The squares represent inventiveethylene/butene copolymers; and the circles represent inventiveethylene/octene copolymers.

FIG. 4 is a plot of octene content of TREF fractionatedethylene/1-octene copolymer fractions versus TREF elution temperature ofthe fraction for the polymer of Example 5 (represented by the circles)and comparative polymers E and F (represented by the “X” symbols). Thediamonds represent traditional random ethylene/octene copolymers.

FIG. 5 is a plot of octene content of TREF fractionatedethylene/1-octene copolymer fractions versus TREF elution temperature ofthe fraction for the polymer of Example 5 (curve 1) and for comparativeF (curve 2). The squares represent Example F*; and the trianglesrepresent Example 5.

FIG. 6 is a graph of the log of storage modulus as a function oftemperature for comparative ethylene/1-octene copolymer (curve 2) andpropylene/ethylene-copolymer (curve 3) and for two ethylene/1-octeneblock copolymers of the invention made with differing quantities ofchain shuttling agent (curves 1).

FIG. 7 shows a plot of TMA (1 mm) versus flex modulus for some inventivepolymers (represented by the diamonds), as compared to some knownpolymers. The triangles represent various Dow VERSIFY® polymers; thecircles represent various random ethylene/styrene copolymers; and thesquares represent various Dow AFFINITY® polymers.

FIG. 8 shows a DSC Overlay: HDPE DMDH 6400+Example A Blends.

FIG. 9 shows a GPC Overlay: HDPE DMDH 6400+Example A Blends.

FIG. 10 shows a Melt Strength Comparison: HDPE DMDH 6400+Example ABlends.

FIG. 11 shows DSC Curves of Inventive and Comparative Samples.

FIG. 12 shows ATREF Curves of Inventive and Comparative Samples.

FIG. 13 shows Notched Izod Impact Dependence on Temperature.

FIG. 14 is a transmission electron micrograph of a mixture ofpolypropylene and an ethylene-octene block copolymer.

FIG. 15 is a transmission electron micrograph of a mixture ofpolypropylene and a random ethylene-octene copolymer.

FIG. 16 is a transmission electron micrograph of a mixture ofpolypropylene, an ethylene-octene block copolymer, and a randomethylene-octene copolymer.

DETAILED DESCRIPTION OF THE INVENTION General Definitions

“Polymer” means a polymeric compound prepared by polymerizing monomers,whether of the same or a different type. The generic term “polymer”embraces the terms “homopolymer,” “copolymer,” “terpolymer” as well as“interpolymer.”

“Interpolymer” means a polymer prepared by the polymerization of atleast two different types of monomers. The generic term “interpolymer”includes the term “copolymer” (which is usually employed to refer to apolymer prepared from two different monomers) as well as the term“terpolymer” (which is usually employed to refer to a polymer preparedfrom three different types of monomers). It also encompasses polymersmade by polymerizing four or more types of monomers.

The term “ethylene/α-olefin interpolymer” generally refers to polymerscomprising ethylene and an α-olefin having 3 or more carbon atoms.Preferably, ethylene comprises the majority mole fraction of the wholepolymer, i.e., ethylene comprises at least about 50 mole percent of thewhole polymer. More preferably ethylene comprises at least about 60 molepercent, at least about 70 mole percent, or at least about 80 molepercent, with the substantial remainder of the whole polymer comprisingat least one other comonomer that is preferably an α-olefin having 3 ormore carbon atoms. For many ethylene/octene copolymers, the preferredcomposition comprises an ethylene content greater than about 80 molepercent of the whole polymer and an octene content of from about 10 toabout 15, preferably from about 15 to about 20 mole percent of the wholepolymer. In some embodiments, the ethylene/α-olefin interpolymers do notinclude those produced in low yields or in a minor amount or as aby-product of a chemical process. While the ethylene/α-olefininterpolymers can be blended with one or more polymers, the as-producedethylene/α-olefin interpolymers are substantially pure and oftencomprise a major component of the reaction product of a polymerizationprocess.

The ethylene/α-olefin interpolymers comprise ethylene and one or morecopolymerizable α-olefin comonomers in polymerized form, characterizedby multiple blocks or segments of two or more polymerized monomer unitsdiffering in chemical or physical properties. That is, theethylene/α-olefin interpolymers are block interpolymers, preferablymulti-block interpolymers or copolymers. The terms “interpolymer” andcopolymer” are used interchangeably herein. In some embodiments, themulti-block copolymer can be represented by the following formula:(AB)_(n)where n is at least 1, preferably an integer greater than 1, such as 2,3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, or higher, “A”represents a hard block or segment and “B” represents a soft block orsegment. Preferably, As and Bs are linked in a substantially linearfashion, as opposed to a substantially branched or substantiallystar-shaped fashion. In other embodiments, A blocks and B blocks arerandomly distributed along the polymer chain. In other words, the blockcopolymers usually do not have a structure as follows.AAA-AA-BBB-BB

In still other embodiments, the block copolymers do not usually have athird type of block, which comprises different comonomer(s). In yetother embodiments, each of block A and block B has monomers orcomonomers substantially randomly distributed within the block. In otherwords, neither block A nor block B comprises two or more sub-segments(or sub-blocks) of distinct composition, such as a tip segment, whichhas a substantially different composition than the rest of the block.

The multi-block polymers typically comprise various amounts of “hard”and “soft” segments. “Hard” segments refer to blocks of polymerizedunits in which ethylene is present in an amount greater than about 95weight percent, and preferably greater than about 98 weight percentbased on the weight of the polymer. In other words, the comonomercontent (content of monomers other than ethylene) in the hard segmentsis less than about 5 weight percent, and preferably less than about 2weight percent based on the weight of the polymer. In some embodiments,the hard segments comprises all or substantially all ethylene. “Soft”segments, on the other hand, refer to blocks of polymerized units inwhich the comonomer content (content of monomers other than ethylene) isgreater than about 5 weight percent, preferably greater than about 8weight percent, greater than about 10 weight percent, or greater thanabout 15 weight percent based on the weight of the polymer. In someembodiments, the comonomer content in the soft segments can be greaterthan about 20 weight percent, greater than about 25 weight percent,greater than about 30 weight percent, greater than about 35 weightpercent, greater than about 40 weight percent, greater than about 45weight percent, greater than about 50 weight percent, or greater thanabout 60 weight percent.

The soft segments can often be present in a block interpolymer fromabout 1 weight percent to about 99 weight percent of the total weight ofthe block interpolymer, preferably from about 5 weight percent to about95 weight percent, from about 10 weight percent to about 90 weightpercent, from about 15 weight percent to about 85 weight percent, fromabout 20 weight percent to about 80 weight percent, from about 25 weightpercent to about 75 weight percent, from about 30 weight percent toabout 70 weight percent, from about 35 weight percent to about 65 weightpercent, from about 40 weight percent to about 60 weight percent, orfrom about 45 weight percent to about 55 weight percent of the totalweight of the block interpolymer. Conversely, the hard segments can bepresent in similar ranges. The soft segment weight percentage and thehard segment weight percentage can be calculated based on data obtainedfrom DSC or NMR. Such methods and calculations are disclosed in aconcurrently filed U.S. patent application Ser. No. 12/558,234, entitled“Ethylene/α-Olefin Block Interpolymers”, filed on Sep. 11, 2009, in thename of Colin L. P. Shan, Lonnie Hazlitt, et. al. and assigned to DowGlobal Technologies Inc., the disclose of which is incorporated byreference herein in its entirety.

The term “crystalline” if employed, refers to a polymer that possesses afirst order transition or crystalline melting point (Tm) as determinedby differential scanning calorimetry (DSC) or equivalent technique. Theterm may be used interchangeably with the term “semicrystalline”. Theterm “amorphous” refers to a polymer lacking a crystalline melting pointas determined by differential scanning calorimetry (DSC) or equivalenttechnique.

The term “multi-block copolymer” or “segmented copolymer” refers to apolymer comprising two or more chemically distinct regions or segments(referred to as “blocks”) preferably joined in a linear manner, that is,a polymer comprising chemically differentiated units which are joinedend-to-end with respect to polymerized ethylenic functionality, ratherthan in pendent or grafted fashion. In a preferred embodiment, theblocks differ in the amount or type of comonomer incorporated therein,the density, the amount of crystallinity, the crystallite sizeattributable to a polymer of such composition, the type or degree oftacticity (isotactic or syndiotactic), regio-regularity orregio-irregularity, the amount of branching, including long chainbranching or hyper-branching, the homogeneity, or any other chemical orphysical property. The multi-block copolymers are characterized byunique distributions of both polydispersity index (PDI or Mw/Mn), blocklength distribution, and/or block number distribution due to the uniqueprocess making of the copolymers. More specifically, when produced in acontinuous process, the polymers desirably possess PDI from 1.7 to 2.9,preferably from 1.8 to 2.5, more preferably from 1.8 to 2.2, and mostpreferably from 1.8 to 2.1. When produced in a batch or semi-batchprocess, the polymers possess PDI from 1.0 to 2.9, preferably from 1.3to 2.5, more preferably from 1.4 to 2.0, and most preferably from 1.4 to1.8.

“Impact-modifying amount of ethylene/α-olefin multi-block interpolymer”is a quantity of ethylene/α-olefin multi-block interpolymer added to agiven polymer composition such that the composition's notched Izodimpact strength at room temperature or below is maintained or increasedas compared to said given composition's notched Izod impact strength atthe same temperature without the added ethylene/α-olefin multi-blockinterpolymer.

In the following description, all numbers disclosed herein areapproximate values, regardless whether the word “about” or “approximate”is used in connection therewith. They may vary by 1 percent, 2 percent,5 percent, or, sometimes, 10 to 20 percent. Whenever a numerical rangewith a lower limit, R^(L) and an upper limit, R^(U), is disclosed, anynumber falling within the range is specifically disclosed. Inparticular, the following numbers within the range are specificallydisclosed: R=R^(L)+k*(R^(U)−R^(L)), wherein k is a variable ranging from1 percent to 100 percent with a 1 percent increment, i.e., k is 1percent, 2 percent, 3 percent, 4 percent, 5 percent, . . . , 50 percent,51 percent, 52 percent, . . . , 95 percent, 96 percent, 97 percent, 98percent, 99 percent, or 100 percent. Moreover, any numerical rangedefined by two R numbers as defined in the above is also specificallydisclosed.

Ethylene/α-Olefin Interpolymers

The ethylene/α-olefin interpolymers used in embodiments of the invention(also referred to as “inventive interpolymer” or “inventive polymer”)comprise ethylene and one or more copolymerizable α-olefin comonomers inpolymerized form, characterized by multiple blocks or segments of two ormore polymerized monomer units differing in chemical or physicalproperties (block interpolymer), preferably a multi-block copolymer. Theethylene/α-olefin interpolymers are characterized by one or more of theaspects described as follows.

In one aspect, the ethylene/α-olefin interpolymers used in embodimentsof the invention have a M_(w)/M_(n) from about 1.7 to about 3.5 and atleast one melting point, T_(m), in degrees Celsius and density, d, ingrams/cubic centimeter, wherein the numerical values of the variablescorrespond to the relationship:T _(m)>−2002.9+4538.5(d)−2422.2(d)², and preferablyT _(m)≧−6288.1+13141(d)−6720.3(d)², and more preferablyT _(m)≧858.91−1825.3(d)+1112.8(d)².

Such melting point/density relationship is illustrated in FIG. 1. Unlikethe traditional random copolymers of ethylene/α-olefins whose meltingpoints decrease with decreasing densities, the inventive interpolymers(represented by diamonds) exhibit melting points substantiallyindependent of the density, particularly when density is between about0.87 g/cc to about 0.95 g/cc. For example, the melting point of suchpolymers are in the range of about 110° C. to about 130° C. when densityranges from 0.875 g/cc to about 0.945 g/cc. In some embodiments, themelting point of such polymers are in the range of about 115° C. toabout 125° C. when density ranges from 0.875 g/cc to about 0.945 g/cc.

In another aspect, the ethylene/α-olefin interpolymers comprise, inpolymerized form, ethylene and one or more α-olefins and arecharacterized by a ΔT, in degree Celsius, defined as the temperature forthe tallest Differential Scanning Calorimetry (“DSC”) peak minus thetemperature for the tallest Crystallization Analysis Fractionation(“CRYSTAF”) peak and a heat of fusion in J/g, ΔH, and ΔT and ΔH satisfythe following relationships:ΔT>−0.1299(ΔH)+62.81, and preferablyΔT≧−0.1299(ΔH)+64.38, and more preferablyΔT≧−0.1299(ΔH)+65.95,for ΔH up to 130 J/g. Moreover, ΔT is equal to or greater than 48° C.for AH greater than 130 J/g. The CRYSTAF peak is determined using atleast 5 percent of the cumulative polymer (that is, the peak mustrepresent at least 5 percent of the cumulative polymer), and if lessthan 5 percent of the polymer has an identifiable CRYSTAF peak, then theCRYSTAF temperature is 30° C., and ΔH is the numerical value of the heatof fusion in J/g. More preferably, the highest CRYSTAF peak contains atleast 10 percent of the cumulative polymer. FIG. 2 shows plotted datafor inventive polymers as well as comparative examples. Integrated peakareas and peak temperatures are calculated by the computerized drawingprogram supplied by the instrument maker. The diagonal line shown forthe random ethylene octene comparative polymers corresponds to theequation ΔT=−0.1299 (ΔH)+62.81.

In yet another aspect, the ethylene/α-olefin interpolymers have amolecular fraction which elutes between 40° C. and 130° C. whenfractionated using Temperature Rising Elution Fractionation (“TREF”),characterized in that said fraction has a molar comonomer contenthigher, preferably at least 5 percent higher, more preferably at least10 percent higher, than that of a comparable random ethyleneinterpolymer fraction eluting between the same temperatures, wherein thecomparable random ethylene interpolymer contains the same comonomer(s),and has a melt index, density, and molar comonomer content (based on thewhole polymer) within 10 percent of that of the block interpolymer.Preferably, the Mw/Mn of the comparable interpolymer is also within 10percent of that of the block interpolymer and/or the comparableinterpolymer has a total comonomer content within 10 weight percent ofthat of the block interpolymer.

In still another aspect, the ethylene/α-olefin interpolymers arecharacterized by an elastic recovery, Re, in percent at 300 percentstrain and 1 cycle measured on a compression-molded film of anethylene/α-olefin interpolymer, and has a density, d, in grams/cubiccentimeter, wherein the numerical values of Re and d satisfy thefollowing relationship when ethylene/α-olefin interpolymer issubstantially free of a cross-linked phase:Re>1481−1629(d); and preferablyRe≧1491−1629(d); and more preferablyRe≧1501−1629(d); and even more preferablyRe≧1511−1629(d).

FIG. 3 shows the effect of density on elastic recovery for unorientedfilms made from certain inventive interpolymers and traditional randomcopolymers. For the same density, the inventive interpolymers havesubstantially higher elastic recoveries.

In some embodiments, the ethylene/α-olefin interpolymers have a tensilestrength above 10 MPa, preferably a tensile strength ≧11 MPa, morepreferably a tensile strength ≧13 MPa and/or an elongation at break ofat least 600 percent, more preferably at least 700 percent, highlypreferably at least 800 percent, and most highly preferably at least 900percent at a crosshead separation rate of 11 cm/minute.

In other embodiments, the ethylene/α-olefin interpolymers have (1) astorage modulus ratio, G′(25° C.)/G′(100° C.), of from 1 to 50,preferably from 1 to 20, more preferably from 1 to 10; and/or (2) a 70°C. compression set of less than 80 percent, preferably less than 70percent, especially less than 60 percent, less than 50 percent, or lessthan 40 percent, down to a compression set of 0 percent.

In still other embodiments, the ethylene/α-olefin interpolymers have a70° C. compression set of less than 80 percent, less than 70 percent,less than 60 percent, or less than 50 percent. Preferably, the 70° C.compression set of the interpolymers is less than 40 percent, less than30 percent, less than 20 percent, and may go down to about 0 percent.

In some embodiments, the ethylene/α-olefin interpolymers have a heat offusion of less than 85 J/g and/or a pellet blocking strength of equal toor less than 100 pounds/foot² (4800 Pa), preferably equal to or lessthan 50 lbs/ft² (2400 Pa), especially equal to or less than 5 lbs/ft²(240 Pa), and as low as 0 lbs/ft² (0 Pa).

In other embodiments, the ethylene/α-olefin interpolymers comprise, inpolymerized form, at least 50 mole percent ethylene and have a 70° C.compression set of less than 80 percent, preferably less than 70 percentor less than 60 percent, most preferably less than 40 to 50 percent anddown to close zero percent.

In some embodiments, the multi-block copolymers possess a PDI fitting aSchultz-Flory distribution rather than a Poisson distribution. Thecopolymers are further characterized as having both a polydisperse blockdistribution and a polydisperse distribution of block sizes andpossessing a most probable distribution of block lengths. Preferredmulti-block copolymers are those containing 4 or more blocks or segmentsincluding terminal blocks. More preferably, the copolymers include atleast 5, 10 or 20 blocks or segments including terminal blocks.

Comonomer content may be measured using any suitable technique, withtechniques based on nuclear magnetic resonance (“NMR”) spectroscopypreferred. Moreover, for polymers or blends of polymers havingrelatively broad TREF curves, the polymer desirably is firstfractionated using TREF into fractions each having an eluted temperaturerange of 10° C. or less. That is, each eluted fraction has a collectiontemperature window of 10° C. or less. Using this technique, said blockinterpolymers have at least one such fraction having a higher molarcomonomer content than a corresponding fraction of the comparableinterpolymer.

In another aspect, the inventive polymer is an olefin interpolymer,preferably comprising ethylene and one or more copolymerizablecomonomers in polymerized form, characterized by multiple blocks (i.e.,at least two blocks) or segments of two or more polymerized monomerunits differing in chemical or physical properties (blockedinterpolymer), most preferably a multi-block copolymer, said blockinterpolymer having a peak (but not just a molecular fraction) whichelutes between 40° C. and 130° C. (but without collecting and/orisolating individual fractions), characterized in that said peak, has acomonomer content estimated by infra-red spectroscopy when expandedusing a full width/half maximum (FWHM) area calculation, has an averagemolar comonomer content higher, preferably at least 5 percent higher,more preferably at least 10 percent higher, than that of a comparablerandom ethylene interpolymer peak at the same elution temperature andexpanded using a full width/half maximum (FWHM) area calculation,wherein said comparable random ethylene interpolymer has the samecomonomer(s) and has a melt index, density, and molar comonomer content(based on the whole polymer) within 10 percent of that of the blockedinterpolymer. Preferably, the Mw/Mn of the comparable interpolymer isalso within 10 percent of that of the blocked interpolymer and/or thecomparable interpolymer has a total comonomer content within 10 weightpercent of that of the blocked interpolymer. The full width/half maximum(FWHM) calculation is based on the ratio of methyl to methylene responsearea [CH₃/CH₂] from the ATREF infra-red detector, wherein the tallest(highest) peak is identified from the base line, and then the FWHM areais determined. For a distribution measured using an ATREF peak, the FWHMarea is defined as the area under the curve between T₁ and T₂, where T₁and T₂ are points determined, to the left and right of the ATREF peak,by dividing the peak height by two, and then drawing a line horizontalto the base line, that intersects the left and right portions of theATREF curve. A calibration curve for comonomer content is made usingrandom ethylene/α-olefin copolymers, plotting comonomer content from NMRversus FWHM area ratio of the TREF peak. For this infra-red method, thecalibration curve is generated for the same comonomer type of interest.The comonomer content of TREF peak of the inventive polymer can bedetermined by referencing this calibration curve using its FWHMmethyl:methylene area ratio [CH₃/CH₂] of the TREF peak.

Comonomer content may be measured using any suitable technique, withtechniques based on nuclear magnetic resonance (NMR) spectroscopypreferred. Using this technique, said blocked interpolymers has highermolar comonomer content than a corresponding comparable interpolymer.

Preferably, for interpolymers of ethylene and 1-octene, the blockinterpolymer has a comonomer content of the TREF fraction elutingbetween 40 and 130° C. greater than or equal to the quantity (−0.2013)T+20.07, more preferably greater than or equal to the quantity (−0.2013)T+21.07, where T is the numerical value of the peak elution temperatureof the TREF fraction being compared, measured in ° C.

FIG. 4 graphically depicts an embodiment of the block interpolymers ofethylene and 1-octene where a plot of the comonomer content versus TREFelution temperature for several comparable ethylene/1-octeneinterpolymers (random copolymers) are fit to a line representing(−0.2013) T+20.07 (solid line). The line for the equation (−0.2013)T+21.07 is depicted by a dotted line. Also depicted are the comonomercontents for fractions of several block ethylene/1-octene interpolymersof the invention (multi-block copolymers). All of the block interpolymerfractions have significantly higher 1-octene content than either line atequivalent elution temperatures. This result is characteristic of theinventive interpolymer and is believed to be due to the presence ofdifferentiated blocks within the polymer chains, having both crystallineand amorphous nature.

FIG. 5 graphically displays the TREF curve and comonomer contents ofpolymer fractions for Example 5 and comparative F to be discussed below.The peak eluting from 40 to 130° C., preferably from 60° C. to 95° C.for both polymers is fractionated into three parts, each part elutingover a temperature range of less than 10° C. Actual data for Example 5is represented by triangles. The skilled artisan can appreciate that anappropriate calibration curve may be constructed for interpolymerscontaining different comonomers and a line used as a comparison fittedto the TREF values obtained from comparative interpolymers of the samemonomers, preferably random copolymers made using a metallocene or otherhomogeneous catalyst composition. Inventive interpolymers arecharacterized by a molar comonomer content greater than the valuedetermined from the calibration curve at the same TREF elutiontemperature, preferably at least 5 percent greater, more preferably atleast 10 percent greater.

In addition to the above aspects and properties described herein, theinventive polymers can be characterized by one or more additionalcharacteristics. In one aspect, the inventive polymer is an olefininterpolymer, preferably comprising ethylene and one or morecopolymerizable comonomers in polymerized form, characterized bymultiple blocks or segments of two or more polymerized monomer unitsdiffering in chemical or physical properties (blocked interpolymer),most preferably a multi-block copolymer, said block interpolymer havinga molecular fraction which elutes between 40° C. and 130° C., whenfractionated using TREF increments, characterized in that said fractionhas a molar comonomer content higher, preferably at least 5 percenthigher, more preferably at least 10, 15, 20 or 25 percent higher, thanthat of a comparable random ethylene interpolymer fraction elutingbetween the same temperatures, wherein said comparable random ethyleneinterpolymer comprises the same comonomer(s), preferably it is the samecomonomer(s), and a melt index, density, and molar comonomer content(based on the whole polymer) within 10 percent of that of the blockedinterpolymer. Preferably, the Mw/Mn of the comparable interpolymer isalso within 10 percent of that of the blocked interpolymer and/or thecomparable interpolymer has a total comonomer content within 10 weightpercent of that of the blocked interpolymer.

Preferably, the above interpolymers are interpolymers of ethylene and atleast one α-olefin, especially those interpolymers having a wholepolymer density from about 0.855 to about 0.935 g/cm³, and moreespecially for polymers having more than about 1 mole percent comonomer,the blocked interpolymer has a comonomer content of the TREF fractioneluting between 40 and 130° C. greater than or equal to the quantity(−0.1356) T+13.89, more preferably greater than or equal to the quantity(−0.1356) T+14.93, and most preferably greater than or equal to thequantity (−0.2013)T+21.07, where T is the numerical value of the peakATREF elution temperature of the TREF fraction being compared, measuredin ° C.

Preferably, for the above interpolymers of ethylene and at least onealpha-olefin especially those interpolymers having a whole polymerdensity from about 0.855 to about 0.935 g/cm³, and more especially forpolymers having more than about 1 mole percent comonomer, the blockedinterpolymer has a comonomer content of the TREF fraction elutingbetween 40 and 130° C. greater than or equal to the quantity (−0.2013)T+20.07, more preferably greater than or equal to the quantity (−0.2013)T+21.07, where T is the numerical value of the peak elution temperatureof the TREF fraction being compared, measured in ° C.

In still another aspect, the inventive polymer is an olefininterpolymer, preferably comprising ethylene and one or morecopolymerizable comonomers in polymerized form, characterized bymultiple blocks or segments of two or more polymerized monomer unitsdiffering in chemical or physical properties (blocked interpolymer),most preferably a multi-block copolymer, said block interpolymer havinga molecular fraction which elutes between 40° C. and 130° C., whenfractionated using TREF increments, characterized in that every fractionhaving a comonomer content of at least about 6 mole percent, has amelting point greater than about 100° C. For those fractions having acomonomer content from about 3 mole percent to about 6 mole percent,every fraction has a DSC melting point of about 110° C. or higher. Morepreferably, said polymer fractions, having at least 1 mol percentcomonomer, has a DSC melting point that corresponds to the equation:Tm≧(−5.5926)(mol percent comonomer in the fraction)+135.90.

In yet another aspect, the inventive polymer is an olefin interpolymer,preferably comprising ethylene and one or more copolymerizablecomonomers in polymerized form, characterized by multiple blocks orsegments of two or more polymerized monomer units differing in chemicalor physical properties (blocked interpolymer), most preferably amulti-block copolymer, said block interpolymer having a molecularfraction which elutes between 40° C. and 130° C., when fractionatedusing TREF increments, characterized in that every fraction that has anATREF elution temperature greater than or equal to about 76° C., has amelt enthalpy (heat of fusion) as measured by DSC, corresponding to theequation:Heat of fusion(J/gm)≦(3.1718)(ATREF elution temperature inCelsius)−136.58,

The inventive block interpolymers have a molecular fraction which elutesbetween 40° C. and 130° C., when fractionated using TREF increments,characterized in that every fraction that has an ATREF elutiontemperature between 40° C. and less than about 76° C., has a meltenthalpy (heat of fusion) as measured by DSC, corresponding to theequation:Heat of fusion(J/gm)≦(1.1312)(ATREF elution temperature inCelsius)+22.97.ATREF Peak Comonomer Composition Measurement by Infra-Red Detector

The comonomer composition of the TREF peak can be measured using an IR4infra-red detector available from Polymer Char, Valencia, Spain(http://www.polymerchar.com).

The “composition mode” of the detector is equipped with a measurementsensor (CH₂) and composition sensor (CH₃) that are fixed narrow bandinfra-red filters in the region of 2800-3000 cm⁻¹. The measurementsensor detects the methylene (CH₂) carbons on the polymer (whichdirectly relates to the polymer concentration in solution) while thecomposition sensor detects the methyl (CH₃) groups of the polymer. Themathematical ratio of the composition signal (CH₃) divided by themeasurement signal (CH₂) is sensitive to the comonomer content of themeasured polymer in solution and its response is calibrated with knownethylene alpha-olefin copolymer standards.

The detector when used with an ATREF instrument provides both aconcentration (CH₂) and composition (CH₃) signal response of the elutedpolymer during the TREF process. A polymer specific calibration can becreated by measuring the area ratio of the CH₃ to CH₂ for polymers withknown comonomer content (preferably measured by NMR). The comonomercontent of an ATREF peak of a polymer can be estimated by applying a thereference calibration of the ratio of the areas for the individual CH₃and CH₂ response (i.e. area ratio CH₃/CH₂ versus comonomer content).

The area of the peaks can be calculated using a full width/half maximum(FWHM) calculation after applying the appropriate baselines to integratethe individual signal responses from the TREF chromatogram. The fullwidth/half maximum calculation is based on the ratio of methyl tomethylene response area [CH₃/CH₂] from the ATREF infra-red detector,wherein the tallest (highest) peak is identified from the base line, andthen the FWHM area is determined. For a distribution measured using anATREF peak, the FWHM area is defined as the area under the curve betweenT1 and T2, where T1 and T2 are points determined, to the left and rightof the ATREF peak, by dividing the peak height by two, and then drawinga line horizontal to the base line, that intersects the left and rightportions of the ATREF curve.

The application of infra-red spectroscopy to measure the comonomercontent of polymers in this ATREF-infra-red method is, in principle,similar to that of GPC/FTIR systems as described in the followingreferences: Markovich, Ronald P.; Hazlitt, Lonnie G.; Smith, Linley;“Development of gel-permeation chromatography-Fourier transform infraredspectroscopy for characterization of ethylene-based polyolefincopolymers”. Polymeric Materials Science and Engineering (1991), 65,98-100.; and Deslauriers, P. J.; Rohlfing, D. C.; Shieh, E. T.;“Quantifying short chain branching microstructures in ethylene-1-olefincopolymers using size exclusion chromatography and Fourier transforminfrared spectroscopy (SEC-FTIR)”, Polymer (2002), 43, 59-170., both ofwhich are incorporated by reference herein in their entirety.

In other embodiments, the inventive ethylene/α-olefin interpolymer ischaracterized by an average block index, ABI, which is greater than zeroand up to about 1.0 and a molecular weight distribution, M_(w)/M_(n),greater than about 1.3. The average block index, ABI, is the weightaverage of the block index (“BI”) for each of the polymer fractionsobtained in preparative TREF from 20° C. and 110° C., with an incrementof 5° C.:ABI=Σ(w _(i) BI _(i))where BI_(i) is the block index for the ith fraction of the inventiveethylene/α-olefin interpolymer obtained in preparative TREF, and w_(i)is the weight percentage of the ith fraction.

For each polymer fraction, BI is defined by one of the two followingequations (both of which give the same BI value):

${BI} = {{\frac{{1/T_{X}} - {1/T_{XO}}}{{1/T_{A}} - {1/T_{AB}}}\mspace{14mu}{or}\mspace{14mu}{BI}} = {- \frac{{LnP}_{X} - {LnP}_{XO}}{{LnP}_{A} - {LnP}_{AB}}}}$where T_(X) is the preparative ATREF elution temperature for the ithfraction (preferably expressed in Kelvin), P_(X) is the ethylene molefraction for the ith fraction, which can be measured by NMR or IR asdescribed above. P_(AB) is the ethylene mole fraction of the wholeethylene/α-olefin interpolymer (before fractionation), which also can bemeasured by NMR or IR. T_(A) and P_(A) are the ATREF elution temperatureand the ethylene mole fraction for pure “hard segments” (which refer tothe crystalline segments of the interpolymer). As a first orderapproximation, the T_(A) and P_(A) values are set to those for highdensity polyethylene homopolymer, if the actual values for the “hardsegments” are not available. For calculations performed herein, T_(A) is372° K., P_(A) is 1.

T_(AB) is the ATREF temperature for a random copolymer of the samecomposition and having an ethylene mole fraction of P_(AB). T_(AB) canbe calculated from the following equation:LnP _(AB) =α/T _(AB)+βwhere α and β are two constants which can be determined by calibrationusing a number of known random ethylene copolymers. It should be notedthat a and β may vary from instrument to instrument. Moreover, one wouldneed to create their own calibration curve with the polymer compositionof interest and also in a similar molecular weight range as thefractions. There is a slight molecular weight effect. If the calibrationcurve is obtained from similar molecular weight ranges, such effectwould be essentially negligible. In some embodiments, random ethylenecopolymers satisfy the following relationship:LnP=−237.83/T _(ATREF)+0.639T_(XO) is the ATREF temperature for a random copolymer of the samecomposition and having an ethylene mole fraction of P_(X). T_(XO) can becalculated from LnP_(X)=α/T_(X)+β. Conversely, P_(XO) is the ethylenemole fraction for a random copolymer of the same composition and havingan ATREF temperature of T_(X), which can be calculated fromLnP_(X)=α/T_(XO)+β.

Once the block index (BI) for each preparative TREF fraction isobtained, the weight average block index, ABI, for the whole polymer canbe calculated. In some embodiments, ABI is greater than zero but lessthan about 0.3 or from about 0.1 to about 0.3. In other embodiments, ABIis greater than about 0.3 and up to about 1.0. Preferably, ABI should bein the range of from about 0.4 to about 0.7, from about 0.5 to about0.7, or from about 0.6 to about 0.9. In some embodiments, ABI is in therange of from about 0.3 to about 0.9, from about 0.3 to about 0.8, orfrom about 0.3 to about 0.7, from about 0.3 to about 0.6, from about 0.3to about 0.5, or from about 0.3 to about 0.4. In other embodiments, ABIis in the range of from about 0.4 to about 1.0, from about 0.5 to about1.0, or from about 0.6 to about 1.0, from about 0.7 to about 1.0, fromabout 0.8 to about 1.0, or from about 0.9 to about 1.0.

Another characteristic of the inventive ethylene/α-olefin interpolymeris that the inventive ethylene/α-olefin interpolymer comprises at leastone polymer fraction which can be obtained by preparative TREF, whereinthe fraction has a block index greater than about 0.1 and up to about1.0 and a molecular weight distribution, M_(w)/M_(n) greater than about1.3. In some embodiments, the polymer fraction has a block index greaterthan about 0.6 and up to about 1.0, greater than about 0.7 and up toabout 1.0, greater than about 0.8 and up to about 1.0, or greater thanabout 0.9 and up to about 1.0. In other embodiments, the polymerfraction has a block index greater than about 0.1 and up to about 1.0,greater than about 0.2 and up to about 1.0, greater than about 0.3 andup to about 1.0, greater than about 0.4 and up to about 1.0, or greaterthan about 0.4 and up to about 1.0. In still other embodiments, thepolymer fraction has a block index greater than about 0.1 and up toabout 0.5, greater than about 0.2 and up to about 0.5, greater thanabout 0.3 and up to about 0.5, or greater than about 0.4 and up to about0.5. In yet other embodiments, the polymer fraction has a block indexgreater than about 0.2 and up to about 0.9, greater than about 0.3 andup to about 0.8, greater than about 0.4 and up to about 0.7, or greaterthan about 0.5 and up to about 0.6.

For copolymers of ethylene and an α-olefin, the inventive polymerspreferably possess (1) a PDI of at least 1.3, more preferably at least1.5, at least 1.7, or at least 2.0, and most preferably at least 2.6, upto a maximum value of 5.0, more preferably up to a maximum of 3.5, andespecially up to a maximum of 2.7; (2) a heat of fusion of 80 J/g orless; (3) an ethylene content of at least 50 weight percent; (4) a glasstransition temperature, T_(g), of less than −25° C., more preferablyless than −30° C., and/or (5) one and only one T_(m).

Further, the inventive polymers can have, alone or in combination withany other properties disclosed herein, a storage modulus, G′, such thatlog (G′) is greater than or equal to 400 kPa, preferably greater than orequal to 1.0 MPa, at a temperature of 100° C. Moreover, the inventivepolymers possess a relatively flat storage modulus as a function oftemperature in the range from 0 to 100° C. (illustrated in FIG. 6) thatis characteristic of block copolymers, and heretofore unknown for anolefin copolymer, especially a copolymer of ethylene and one or moreC₃₋₈ aliphatic α-olefins. (By the term “relatively flat” in this contextis meant that log G′ (in Pascals) decreases by less than one order ofmagnitude between 50 and 100° C., preferably between 0 and 100° C.).

The inventive interpolymers may be further characterized by athermomechanical analysis penetration depth of 1 mm at a temperature ofat least 90° C. as well as a flexural modulus of from 3 kpsi (20 MPa) to13 kpsi (90 MPa). Alternatively, the inventive interpolymers can have athermomechanical analysis penetration depth of 1 mm at a temperature ofat least 104° C. as well as a flexural modulus of at least 3 kpsi (20MPa). They may be characterized as having an abrasion resistance (orvolume loss) of less than 90 mm³. FIG. 7 shows the TMA (1 mm) versusflex modulus for the inventive polymers, as compared to other knownpolymers. The inventive polymers have significantly betterflexibility-heat resistance balance than the other polymers.

Additionally, the ethylene/α-olefin interpolymers can have a melt index,12, from 0.01 to 2000 g/10 minutes, preferably from 0.01 to 1000 g/10minutes, more preferably from 0.01 to 500 g/10 minutes, and especiallyfrom 0.01 to 100 g/10 minutes. In certain embodiments, theethylene/α-olefin interpolymers have a melt index, I₂, from 0.01 to 10g/10 minutes, from 0.5 to 50 g/10 minutes, from 1 to 30 g/10 minutes,from 1 to 6 g/10 minutes or from 0.3 to 10 g/10 minutes. In certainembodiments, the melt index for the ethylene/α-olefin polymers is 1 g/10minutes, 3 g/10 minutes or 5 g/10 minutes.

The polymers can have molecular weights, M_(w), from 1,000 g/mole to5,000,000 g/mole, preferably from 1000 g/mole to 1,000,000, morepreferably from 10,000 g/mole to 500,000 g/mole, and especially from10,000 g/mole to 300,000 g/mole. The density of the inventive polymerscan be from 0.80 to 0.99 g/cm³ and preferably for ethylene containingpolymers from 0.85 g/cm³ to 0.97 g/cm³. In certain embodiments, thedensity of the ethylene/α-olefin polymers ranges from 0.860 to 0.925g/cm³ or 0.867 to 0.910 g/cm³.

The process of making the polymers has been disclosed in the followingpatent applications: U.S. Provisional Application No. 60/553,906, filedMar. 17, 2004; U.S. Provisional Application No. 60/662,937, filed Mar.17, 2005; U.S. Provisional Application No. 60/662,939, filed Mar. 17,2005; U.S. Provisional Application No. 60/566,2938, filed Mar. 17, 2005;PCT Application No. PCT/US2005/008916, filed Mar. 17, 2005; PCTApplication No. PCT/US2005/008915, filed Mar. 17, 2005; and PCTApplication No. PCT/US2005/008917, filed Mar. 17, 2005, all of which areincorporated by reference herein in their entirety. For example, onesuch method comprises contacting ethylene and optionally one or moreaddition polymerizable monomers other than ethylene under additionpolymerization conditions with a catalyst composition comprising:

the admixture or reaction product resulting from combining:

(A) a first olefin polymerization catalyst having a high comonomerincorporation index,

(B) a second olefin polymerization catalyst having a comonomerincorporation index less than 90 percent, preferably less than 50percent, most preferably less than 5 percent of the comonomerincorporation index of catalyst (A), and

(C) a chain shuttling agent.

Representative catalysts and chain shuttling agent are as follows.

Catalyst (A1) is[N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafniumdimethyl, prepared according to the teachings of WO 03/40195,2003US0204017, U.S. Ser. No. 10/429,024, filed May 2, 2003, and WO04/24740.

Catalyst (A2) is[N-(2,6-di(1-methylethyl)phenyl)amido)(2-methylphenyl)(1,2-phenylene-(6-pyridin-2-diyl)methane)]hafniumdimethyl, prepared according to the teachings of WO 03/40195,2003US0204017, U.S. Ser. No. 10/429,024, filed May 2, 2003, and WO04/24740.

Catalyst (A3) isbis[N,N′″-(2,4,6-tri(methylphenyl)amido)ethylenediamine]hafniumdibenzyl.

Catalyst (A4) isbis((2-oxoyl-3-(dibenzo-1H-pyrrole-1-yl)-5-(methyl)phenyl)-2-phenoxymethyl)cyclohexane-1,2-diylzirconium (IV) dibenzyl, prepared substantially according to theteachings of US-A-2004/0010103.

Catalyst (B1) is1,2-bis-(3,5-di-t-butylphenylene)(1-(N-(1-methylethyl)immino)methyl)(2-oxoyl)zirconiumdibenzyl

Catalyst (B2) is1,2-bis-(3,5-di-t-butylphenylene)(1-(N-(2-methylcyclohexyl)-immino)methyl)(2-oxoyl)zirconiumdibenzyl

Catalyst (C1) is(t-butylamido)dimethyl(3-N-pyrrolyl-1,2,3,3a,7a-η-inden-1-yl)silanetitaniumdimethyl prepared substantially according to the techniques of U.S. Pat.No. 6,268,444:

Catalyst (C2) is(t-butylamido)di(4-methylphenyl)(2-methyl-1,2,3,3a,7a-η-inden-1-yl)silanetitaniumdimethyl prepared substantially according to the teachings ofUS-A-2003/004286:

Catalyst (C3) is(t-butylamido)di(4-methylphenyl)(2-methyl-1,2,3,3a,8a-η-s-indacen-1-yl)silanetitaniumdimethyl prepared substantially according to the teachings ofUS-A-2003/004286:

Catalyst (D1) is bis(dimethyldisiloxane)(indene-1-yl)zirconiumdichloride available from Sigma-Aldrich:

Shuttling Agents The shuttling agents employed include diethylzinc,di(i-butyl)zinc, di(n-hexyl)zinc, triethylaluminum, trioctylaluminum,triethylgallium, i-butylaluminum bis(dimethyl(t-butyl)siloxane),i-butylaluminum bis(di(trimethylsilyl)amide), n-octylaluminumdi(pyridine-2-methoxide), bis(n-octadecyl)i-butylaluminum,i-butylaluminum bis(di(n-pentyl)amide), n-octylaluminumbis(2,6-di-t-butylphenoxide, n-octylaluminum di(ethyl(1-naphthyl)amide),ethylaluminum bis(t-butyldimethylsiloxide), ethylaluminumdi(bis(trimethylsilyl)amide), ethylaluminumbis(2,3,6,7-dibenzo-1-azacycloheptaneamide), n-octylaluminumbis(2,3,6,7-dibenzo-1-azacycloheptaneamide), n-octylaluminumbis(dimethyl(t-butyl)siloxide, ethylzinc (2,6-diphenylphenoxide), andethylzinc (t-butoxide).

Preferably, the foregoing process takes the form of a continuoussolution process for forming block copolymers, especially multi-blockcopolymers, preferably linear multi-block copolymers of two or moremonomers, more especially ethylene and a C₃₋₂₀ olefin or cycloolefin,and most especially ethylene and a C₄₋₂₀ α-olefin, using multiplecatalysts that are incapable of interconversion. That is, the catalystsare chemically distinct. Under continuous solution polymerizationconditions, the process is ideally suited for polymerization of mixturesof monomers at high monomer conversions. Under these polymerizationconditions, shuttling from the chain shuttling agent to the catalystbecomes advantaged compared to chain growth, and multi-block copolymers,especially linear multi-block copolymers are formed in high efficiency.

The inventive interpolymers may be differentiated from conventional,random copolymers, physical blends of polymers, and block copolymersprepared via sequential monomer addition, fluxional catalysts, anionicor cationic living polymerization techniques. In particular, compared toa random copolymer of the same monomers and monomer content atequivalent crystallinity or modulus, the inventive interpolymers havebetter (higher) heat resistance as measured by melting point, higher TMApenetration temperature, higher high-temperature tensile strength,and/or higher high-temperature torsion storage modulus as determined bydynamic mechanical analysis. Compared to a random copolymer containingthe same monomers and monomer content, the inventive interpolymers havelower compression set, particularly at elevated temperatures, lowerstress relaxation, higher creep resistance, higher tear strength, higherblocking resistance, faster setup due to higher crystallization(solidification) temperature, higher recovery (particularly at elevatedtemperatures), better abrasion resistance, higher retractive force, andbetter oil and filler acceptance.

The inventive interpolymers also exhibit a unique crystallization andbranching distribution relationship. That is, the inventiveinterpolymers have a relatively large difference between the tallestpeak temperature measured using CRYSTAF and DSC as a function of heat offusion, especially as compared to random copolymers containing the samemonomers and monomer level or physical blends of polymers, such as ablend of a high density polymer and a lower density copolymer, atequivalent overall density. It is believed that this unique feature ofthe inventive interpolymers is due to the unique distribution of thecomonomer in blocks within the polymer backbone. In particular, theinventive interpolymers may comprise alternating blocks of differingcomonomer content (including homopolymer blocks). The inventiveinterpolymers may also comprise a distribution in number and/or blocksize of polymer blocks of differing density or comonomer content, whichis a Schultz-Flory type of distribution. In addition, the inventiveinterpolymers also have a unique peak melting point and crystallizationtemperature profile that is substantially independent of polymerdensity, modulus, and morphology. In a preferred embodiment, themicrocrystalline order of the polymers demonstrates characteristicspherulites and lamellae that are distinguishable from random or blockcopolymers, even at PDI values that are less than 1.7, or even less than1.5, down to less than 1.3.

Moreover, the inventive interpolymers may be prepared using techniquesto influence the degree or level of blockiness. That is the amount ofcomonomer and length of each polymer block or segment can be altered bycontrolling the ratio and type of catalysts and shuttling agent as wellas the temperature of the polymerization, and other polymerizationvariables. A surprising benefit of this phenomenon is the discovery thatas the degree of blockiness is increased, the optical properties, tearstrength, and high temperature recovery properties of the resultingpolymer are improved. In particular, haze decreases while clarity, tearstrength, and high temperature recovery properties increase as theaverage number of blocks in the polymer increases. By selectingshuttling agents and catalyst combinations having the desired chaintransferring ability (high rates of shuttling with low levels of chaintermination) other forms of polymer termination are effectivelysuppressed. Accordingly, little if any β-hydride elimination is observedin the polymerization of ethylene/α-olefin comonomer mixtures accordingto embodiments of the invention, and the resulting crystalline blocksare highly, or substantially completely, linear, possessing little or nolong chain branching.

Polymers with highly crystalline chain ends can be selectively preparedin accordance with embodiments of the invention. In elastomerapplications, reducing the relative quantity of polymer that terminateswith an amorphous block reduces the intermolecular dilutive effect oncrystalline regions. This result can be obtained by choosing chainshuttling agents and catalysts having an appropriate response tohydrogen or other chain terminating agents. Specifically, if thecatalyst which produces highly crystalline polymer is more susceptibleto chain termination (such as by use of hydrogen) than the catalystresponsible for producing the less crystalline polymer segment (such asthrough higher comonomer incorporation, regio-error, or atactic polymerformation), then the highly crystalline polymer segments willpreferentially populate the terminal portions of the polymer. Not onlyare the resulting terminated groups crystalline, but upon termination,the highly crystalline polymer forming catalyst site is once againavailable for reinitiation of polymer formation. The initially formedpolymer is therefore another highly crystalline polymer segment.Accordingly, both ends of the resulting multi-block copolymer arepreferentially highly crystalline.

The ethylene α-olefin interpolymers used in the embodiments of theinvention are preferably interpolymers of ethylene with at least oneC₃-C₂₀ α-olefin. Copolymers of ethylene and a C₃-C₂₀α-olefin areespecially preferred. The interpolymers may further comprise C₄-C₁₈diolefin and/or alkenylbenzene. Suitable unsaturated comonomers usefulfor polymerizing with ethylene include, for example, ethylenicallyunsaturated monomers, conjugated or nonconjugated dienes, polyenes,alkenylbenzenes, etc. Examples of such comonomers include C₃-C₂₀α-olefins such as propylene, isobutylene, 1-butene, 1-hexene, 1-pentene,4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, and thelike. 1-Butene and 1-octene are especially preferred. Other suitablemonomers include styrene, halo- or alkyl-substituted styrenes,vinylbenzocyclobutane, 1,4-hexadiene, 1,7-octadiene, and naphthenics(e.g., cyclopentene, cyclohexene and cyclooctene).

While ethylene/α-olefin interpolymers are preferred polymers, otherethylene/olefin polymers may also be used. Olefins as used herein referto a family of unsaturated hydrocarbon-based compounds with at least onecarbon-carbon double bond. Depending on the selection of catalysts, anyolefin may be used in embodiments of the invention. Preferably, suitableolefins are C₃-C₂₀ aliphatic and aromatic compounds containing vinylicunsaturation, as well as cyclic compounds, such as cyclobutene,cyclopentene, dicyclopentadiene, and norbornene, including but notlimited to, norbornene substituted in the 5 and 6 position with C₁-C₂₀hydrocarbyl or cyclohydrocarbyl groups. Also included are mixtures ofsuch olefins as well as mixtures of such olefins with C₄-C₄₀ diolefincompounds.

Examples of olefin monomers include, but are not limited to propylene,isobutylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene,1-nonene, 1-decene, and 1-dodecene, 1-tetradecene, 1-hexadecene,1-octadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene,4-methyl-1-pentene, 4,6-dimethyl-1-heptene, 4-vinylcyclohexene,vinylcyclohexane, norbornadiene, ethylidene norbornene, cyclopentene,cyclohexene, dicyclopentadiene, cyclooctene, C₄-C₄₀ dienes, includingbut not limited to 1,3-butadiene, 1,3-pentadiene, 1,4-hexadiene,1,5-hexadiene, 1,7-octadiene, 1,9-decadiene, other C₄-C₄₀ α-olefins, andthe like. In certain embodiments, the α-olefin is propylene, 1-butene,1-pentene, 1-hexene, 1-octene or a combination thereof. Although anyhydrocarbon containing a vinyl group potentially may be used inembodiments of the invention, practical issues such as monomeravailability, cost, and the ability to conveniently remove unreactedmonomer from the resulting polymer may become more problematic as themolecular weight of the monomer becomes too high.

The polymerization processes described herein are well suited for theproduction of olefin polymers comprising monovinylidene aromaticmonomers including styrene, o-methyl styrene, p-methyl styrene,t-butylstyrene, and the like. In particular, interpolymers comprisingethylene and styrene can be prepared by following the teachings herein.Optionally, copolymers comprising ethylene, styrene and a C₃-C₂₀ alphaolefin, optionally comprising a C₄-C₂₀ diene, having improved propertiescan be prepared.

Suitable non-conjugated diene monomers can be a straight chain, branchedchain or cyclic hydrocarbon diene having from 6 to 15 carbon atoms.Examples of suitable non-conjugated dienes include, but are not limitedto, straight chain acyclic dienes, such as 1,4-hexadiene, 1,6-octadiene,1,7-octadiene, 1,9-decadiene, branched chain acyclic dienes, such as5-methyl-1,4-hexadiene; 3,7-dimethyl-1,6-octadiene;3,7-dimethyl-1,7-octadiene and mixed isomers of dihydromyricene anddihydroocinene, single ring alicyclic dienes, such as1,3-cyclopentadiene; 1,4-cyclohexadiene; 1,5-cyclooctadiene and1,5-cyclododecadiene, and multi-ring alicyclic fused and bridged ringdienes, such as tetrahydroindene, methyl tetrahydroindene,dicyclopentadiene, bicyclo-(2,2,1)-hepta-2,5-diene; alkenyl, alkylidene,cycloalkenyl and cycloalkylidene norbornenes, such as5-methylene-2-norbornene (MNB); 5-propenyl-2-norbornene,5-isopropylidene-2-norbornene, 5-(4-cyclopentenyl)-2-norbornene,5-cyclohexylidene-2-norbornene, 5-vinyl-2-norbornene, and norbornadiene.Of the dienes typically used to prepare EPDMs, the particularlypreferred dienes are 1,4-hexadiene (HD), 5-ethylidene-2-norbornene(ENB), 5-vinylidene-2-norbornene (VNB), 5-methylene-2-norbornene (MNB),and dicyclopentadiene (DCPD). The especially preferred dienes are5-ethylidene-2-norbornene (ENB) and 1,4-hexadiene (HD).

One class of desirable polymers that can be made in accordance withembodiments of the invention are elastomeric interpolymers of ethylene,a C₃-C₂₀ α-olefin, especially propylene, and optionally one or morediene monomers. Preferred α-olefins for use in this embodiment of thepresent invention are designated by the formula CH₂═CHR*, where R* is alinear or branched alkyl group of from 1 to 12 carbon atoms. Examples ofsuitable α-olefins include, but are not limited to, propylene,isobutylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and1-octene. A particularly preferred α-olefin is propylene. The propylenebased polymers are generally referred to in the art as EP or EPDMpolymers. Suitable dienes for use in preparing such polymers, especiallymulti-block EPDM type polymers include conjugated or non-conjugated,straight or branched chain-, cyclic- or polycyclic-dienes comprisingfrom 4 to 20 carbons. Preferred dienes include 1,4-pentadiene,1,4-hexadiene, 5-ethylidene-2-norbornene, dicyclopentadiene,cyclohexadiene, and 5-butylidene-2-norbornene. A particularly preferreddiene is 5-ethylidene-2-norbornene.

Because the diene containing polymers comprise alternating segments orblocks containing greater or lesser quantities of the diene (includingnone) and α-olefin (including none), the total quantity of diene andα-olefin may be reduced without loss of subsequent polymer properties.That is, because the diene and α-olefin monomers are preferentiallyincorporated into one type of block of the polymer rather than uniformlyor randomly throughout the polymer, they are more efficiently utilizedand subsequently the crosslink density of the polymer can be bettercontrolled. Such crosslinkable elastomers and the cured products haveadvantaged properties, including higher tensile strength and betterelastic recovery.

In some embodiments, the inventive interpolymers made with two catalystsincorporating differing quantities of comonomer have a weight ratio ofblocks formed thereby from 95:5 to 5:95. The elastomeric polymersdesirably have an ethylene content of from 20 to 90 percent, a dienecontent of from 0.1 to 10 percent, and an α-olefin content of from 10 to80 percent, based on the total weight of the polymer. Furtherpreferably, the multi-block elastomeric polymers have an ethylenecontent of from 60 to 90 percent, a diene content of from 0.1 to 10percent, and an α-olefin content of from 10 to 40 percent, based on thetotal weight of the polymer. Preferred polymers are high molecularweight polymers, having a weight average molecular weight (Mw) from10,000 to about 2,500,000, preferably from 20,000 to 500,000, morepreferably from 20,000 to 350,000, and a polydispersity less than 3.5,more preferably less than 3.0, and a Mooney viscosity (ML (1+4) 125° C.)from 1 to 250. More preferably, such polymers have an ethylene contentfrom 65 to 75 percent, a diene content from 0 to 6 percent, and anα-olefin content from 20 to 35 percent.

The ethylene/α-olefin interpolymers can be functionalized byincorporating at least one functional group in its polymer structure.Exemplary functional groups may include, for example, ethylenicallyunsaturated mono- and di-functional carboxylic acids, ethylenicallyunsaturated mono- and di-functional carboxylic acid anhydrides, saltsthereof and esters thereof. Such functional groups may be grafted to anethylene/α-olefin interpolymer, or it may be copolymerized with ethyleneand an optional additional comonomer to form an interpolymer ofethylene, the functional comonomer and optionally other comonomer(s).Means for grafting functional groups onto polyethylene are described forexample in U.S. Pat. Nos. 4,762,890, 4,927,888, and 4,950,541, thedisclosures of these patents are incorporated herein by reference intheir entirety. One particularly useful functional group is malicanhydride.

The amount of the functional group present in the functionalinterpolymer can vary. The functional group can typically be present ina copolymer-type functionalized interpolymer in an amount of at leastabout 1.0 weight percent, preferably at least about 5 weight percent,and more preferably at least about 7 weight percent. The functionalgroup will typically be present in a copolymer-type functionalizedinterpolymer in an amount less than about 40 weight percent, preferablyless than about 30 weight percent, and more preferably less than about25 weight percent.

Testing Methods

In the examples that follow, the following analytical techniques areemployed:

GPC Method for Samples 1-4 and A-C

An automated liquid-handling robot equipped with a heated needle set to160° C. is used to add enough 1,2,4-trichlorobenzene stabilized with 300ppm Ionol to each dried polymer sample to give a final concentration of30 mg/mL. A small glass stir rod is placed into each tube and thesamples are heated to 160° C. for 2 hours on a heated, orbital-shakerrotating at 250 rpm. The concentrated polymer solution is then dilutedto 1 mg/ml using the automated liquid-handling robot and the heatedneedle set to 160° C.

A Symyx Rapid GPC system is used to determine the molecular weight datafor each sample. A Gilson 350 pump set at 2.0 ml/min flow rate is usedto pump helium-purged 1,2-dichlorobenzene stabilized with 300 ppm Ionolas the mobile phase through three Plgel 10 micrometer (μm) Mixed B 300mm×7.5 mm columns placed in series and heated to 160° C. A Polymer LabsELS 1000 Detector is used with the Evaporator set to 250° C., theNebulizer set to 165° C., and the nitrogen flow rate set to 1.8 SLM at apressure of 60-80 psi (400-600 kPa) N₂. The polymer samples are heatedto 160° C. and each sample injected into a 250 μl loop using theliquid-handling robot and a heated needle. Serial analysis of thepolymer samples using two switched loops and overlapping injections areused. The sample data is collected and analyzed using Symyx Epoch™software. Peaks are manually integrated and the molecular weightinformation reported uncorrected against a polystyrene standardcalibration curve.

Standard CRYSTAF Method

Branching distributions are determined by crystallization analysisfractionation (CRYSTAF) using a CRYSTAF 200 unit commercially availablefrom PolymerChar, Valencia, Spain. The samples are dissolved in 1,2,4trichlorobenzene at 160° C. (0.66 mg/mL) for 1 hr and stabilized at 95°C. for 45 minutes. The sampling temperatures range from 95 to 30° C. ata cooling rate of 0.2° C./min. An infrared detector is used to measurethe polymer solution concentrations. The cumulative solubleconcentration is measured as the polymer crystallizes while thetemperature is decreased. The analytical derivative of the cumulativeprofile reflects the short chain branching distribution of the polymer.

The CRYSTAF peak temperature and area are identified by the peakanalysis module included in the CRYSTAF Software (Version 2001.b,PolymerChar, Valencia, Spain). The CRYSTAF peak finding routineidentifies a peak temperature as a maximum in the dW/dT curve and thearea between the largest positive inflections on either side of theidentified peak in the derivative curve. To calculate the CRYSTAF curve,the preferred processing parameters are with a temperature limit of 70°C. and with smoothing parameters above the temperature limit of 0.1, andbelow the temperature limit of 0.3.

DSC Standard Method (Excluding Samples 1-4 and A-C)

Differential Scanning Calorimetry results are determined using a TAImodel Q1000 DSC equipped with an RCS cooling accessory and anautosampler. A nitrogen purge gas flow of 50 ml/min is used. The sampleis pressed into a thin film and melted in the press at about 175° C. andthen air-cooled to room temperature (25° C.). 3-10 mg of material isthen cut into a 6 mm diameter disk, accurately weighed, placed in alight aluminum pan (ca 50 mg), and then crimped shut. The thermalbehavior of the sample is investigated with the following temperatureprofile. The sample is rapidly heated to 180° C. and held isothermal for3 minutes in order to remove any previous thermal history. The sample isthen cooled to −40° C. at 10° C./min cooling rate and held at −40° C.for 3 minutes. The sample is then heated to 150° C. at 10° C./min.heating rate. The cooling and second heating curves are recorded.

The DSC melting peak is measured as the maximum in heat flow rate (W/g)with respect to the linear baseline drawn between −30° C. and end ofmelting. The heat of fusion is measured as the area under the meltingcurve between −30° C. and the end of melting using a linear baseline.

GPC Method (Excluding Samples 1-4 and A-C)

The gel permeation chromatographic system consists of either a PolymerLaboratories Model PL-210 or a Polymer Laboratories Model PL-220instrument. The column and carousel compartments are operated at 140° C.Three Polymer Laboratories 10-micron Mixed-B columns are used. Thesolvent is 1,2,4 trichlorobenzene. The samples are prepared at aconcentration of 0.1 grams of polymer in 50 milliliters of solventcontaining 200 ppm of butylated hydroxytoluene (BHT). Samples areprepared by agitating lightly for 2 hours at 160° C. The injectionvolume used is 100 microliters and the flow rate is 1.0 ml/minute.

Calibration of the GPC column set is performed with 21 narrow molecularweight distribution polystyrene standards with molecular weights rangingfrom 580 to 8,400,000, arranged in 6 “cocktail” mixtures with at least adecade of separation between individual molecular weights. The standardsare purchased from Polymer Laboratories (Shropshire, UK). Thepolystyrene standards are prepared at 0.025 grams in 50 milliliters ofsolvent for molecular weights equal to or greater than 1,000,000, and0.05 grams in 50 milliliters of solvent for molecular weights less than1,000,000. The polystyrene standards are dissolved at 80° C. with gentleagitation for 30 minutes. The narrow standards mixtures are run firstand in order of decreasing highest molecular weight component tominimize degradation. The polystyrene standard peak molecular weightsare converted to polyethylene molecular weights using the followingequation (as described in Williams and Ward, J. Polym. Sci. Polym. Let.,6, 621 (1968)): M_(polyethylene)=0.431(M_(polystyrene)).

Polyethylene equivalent molecular weight calculations are performedusing Viscotek TriSEC software Version 3.0.

Compression Set

Compression set is measured according to ASTM D 395. The sample isprepared by stacking 25.4 mm diameter round discs of 3.2 mm, 2.0 mm, and0.25 mm thickness until a total thickness of 12.7 mm is reached. Thediscs are cut from 12.7 cm×12.7 cm compression molded plaques moldedwith a hot press under the following conditions: zero pressure for 3 minat 190° C., followed by 86 MPa for 2 min at 190° C., followed by coolinginside the press with cold running water at 86 MPa.

Density

Samples for density measurement are prepared according to ASTM D 1928.Measurements are made within one hour of sample pressing using ASTMD792, Method B.

Flexural/Secant Modulus/Storage Modulus

Samples are compression molded using ASTM D 1928. Flexural and 2 percentsecant moduli are measured according to ASTM D-790. Storage modulus ismeasured according to ASTM D 5026-01 or equivalent technique.

Optical Properties

Films of 0.4 mm thickness are compression molded using a hot press(Carver Model #4095-4PR1001R). The pellets are placed betweenpolytetrafluoroethylene sheets, heated at 190° C. at 55 psi (380 kPa)for 3 min, followed by 1.3 MPa for 3 min, and then 2.6 MPa for 3 min.The film is then cooled in the press with running cold water at 1.3 MPafor 1 min. The compression molded films are used for opticalmeasurements, tensile behavior, recovery, and stress relaxation.

Clarity is measured using BYK Gardner Haze-gard as specified in ASTM D1746.

gloss is measured using BYK Gardner Glossmeter Microgloss 45° asspecified in ASTM D-2457

Internal haze is measured using BYK Gardner Haze-gard based on ASTM D1003 Procedure A. Mineral oil is applied to the film surface to removesurface scratches.

Mechanical Properties—Tensile, Hysteresis, and Tear

Stress-strain behavior in uniaxial tension is measured using ASTM D 1708microtensile specimens. Samples are stretched with an Instron at 500%min⁻¹ at 21° C. Tensile strength and elongation at break are reportedfrom an average of 5 specimens.

100% and 300% Hysteresis is determined from cyclic loading to 100% and300% strains using ASTM D 1708 microtensile specimens with an Instron™instrument. The sample is loaded and unloaded at 267% min⁻¹ for 3 cyclesat 21° C. Cyclic experiments at 300% and 80° C. are conducted using anenvironmental chamber. In the 80° C. experiment, the sample is allowedto equilibrate for 45 minutes at the test temperature before testing. Inthe 21° C., 300% strain cyclic experiment, the retractive stress at 150%strain from the first unloading cycle is recorded. Percent recovery forall experiments are calculated from the first unloading cycle using thestrain at which the load returned to the base line. The percent recoveryis defined as:

${\%\mspace{14mu}{Recovery}} = {\frac{ɛ_{f} - ɛ_{s}}{ɛ_{f}} \times 100}$where ε_(f) is the strain taken for cyclic loading and ε_(s) is thestrain where the load returns to the baseline during the 1^(st)unloading cycle.

Stress relaxation is measured at 50 percent strain and 37° C. for 12hours using an Instron™ instrument equipped with an environmentalchamber. The gauge geometry was 76 mm×25 mm×0.4 mm. After equilibratingat 37° C. for 45 min in the environmental chamber, the sample wasstretched to 50% strain at 333% min⁻¹. Stress was recorded as a functionof time for 12 hours. The percent stress relaxation after 12 hours wascalculated using the formula:

${\%\mspace{14mu}{Stress}\mspace{14mu}{Relaxation}} = {\frac{L_{0} - L_{12}}{L_{0}} \times 100}$where L₀ is the load at 50% strain at 0 time and L₁₂ is the load at 50percent strain after 12 hours.

Tensile notched tear experiments are carried out on samples having adensity of 0.88 g/cc or less using an Instron™ instrument. The geometryconsists of a gauge section of 76 mm×13 mm×0.4 mm with a 2 mm notch cutinto the sample at half the specimen length. The sample is stretched at508 mm min⁻¹ at 21° C. until it breaks. The tear energy is calculated asthe area under the stress-elongation curve up to strain at maximum load.An average of at least 3 specimens are reported.

TMA

Thermal Mechanical Analysis (Penetration Temperature) is conducted on 30mm diameter×3.3 mm thick, compression molded discs, formed at 180° C.and 10 MPa molding pressure for 5 minutes and then air quenched. Theinstrument used is a TMA 7, brand available from Perkin-Elmer. In thetest, a probe with 1.5 mm radius tip (P/N N519-0416) is applied to thesurface of the sample disc with 1N force. The temperature is raised at5° C./min from 25° C. The probe penetration distance is measured as afunction of temperature. The experiment ends when the probe haspenetrated 1 mm into the sample.

DMA

Dynamic Mechanical Analysis (DMA) is measured on compression moldeddisks formed in a hot press at 180° C. at 10 MPa pressure for 5 minutesand then water cooled in the press at 90° C./min. Testing is conductedusing an ARES controlled strain rheometer (TA instruments) equipped withdual cantilever fixtures for torsion testing.

A 1.5 mm plaque is pressed and cut in a bar of dimensions 32×12 mm. Thesample is clamped at both ends between fixtures separated by 10 mm (gripseparation ΔL) and subjected to successive temperature steps from −100°C. to 200° C. (5° C. per step). At each temperature the torsion modulusG′ is measured at an angular frequency of 10 rad/s, the strain amplitudebeing maintained between 0.1 percent and 4 percent to ensure that thetorque is sufficient and that the measurement remains in the linearregime.

An initial static force of 10 g is maintained (auto-tension mode) toprevent slack in the sample when thermal expansion occurs. As aconsequence, the grip separation ΔL increases with the temperature,particularly above the melting or softening point of the polymer sample.The test stops at the maximum temperature or when the gap between thefixtures reaches 65 mm.

Melt Index

Melt index, or 12, is measured in accordance with ASTM D 1238, Condition190° C./2.16 kg. Melt index, or I₁₀ is also measured in accordance withASTM D 1238, Condition 190° C./10 kg.

ATREF

Analytical temperature rising elution fractionation (ATREF) analysis isconducted according to the method described in U.S. Pat. No. 4,798,081and Wilde, L.; Ryle, T. R.; Knobeloch, D. C.; Peat, I. R.; Determinationof Branching Distributions in Polyethylene and Ethylene Copolymers, J.Polym. Sci., 20, 441-455 (1982), which are incorporated by referenceherein in their entirety. The composition to be analyzed is dissolved intrichlorobenzene and allowed to crystallize in a column containing aninert support (stainless steel shot) by slowly reducing the temperatureto 20° C. at a cooling rate of 0.1° C./min. The column is equipped withan infrared detector. An ATREF chromatogram curve is then generated byeluting the crystallized polymer sample from the column by slowlyincreasing the temperature of the eluting solvent (trichlorobenzene)from 20 to 120° C. at a rate of 1.5° C./min.

¹³C NMR Analysis

The samples are prepared by adding approximately 3 g of a 50/50 mixtureof tetrachloroethane-d²/orthodichlorobenzene to 0.4 g sample in a 10 mmNMR tube. The samples are dissolved and homogenized by heating the tubeand its contents to 150° C. The data are collected using a JEOL Eclipse™400 MHz spectrometer or a Varian Unity Plus™ 400 MHz spectrometer,corresponding to a ¹³C resonance frequency of 100.5 MHz. The data areacquired using 4000 transients per data file with a 6 second pulserepetition delay. To achieve minimum signal-to-noise for quantitativeanalysis, multiple data files are added together. The spectral width is25,000 Hz with a minimum file size of 32K data points. The samples areanalyzed at 130° C. in a 10 mm broad band probe. The comonomerincorporation is determined using Randall's triad method (Randall, J.C.; JMS-Rev. Macromol. Chem. Phys., C29, 201-317 (1989), which isincorporated by reference herein in its entirety.

Polymer Fractionation by TREF

Large-scale TREF fractionation is carried by dissolving 15-20 g ofpolymer in 2 liters of 1,2,4-trichlorobenzene (TCB) by stirring for 4hours at 160° C. The polymer solution is forced by 15 psig (100 kPa)nitrogen onto a 3 inch by 4 foot (7.6 cm×12 cm) steel column packed witha 60:40 (v:v) mix of 30-40 mesh (600-425 μm) spherical, technicalquality glass beads (available from Potters Industries, HC 30 Box 20,Brownwood, Tex., 76801) and stainless steel, 0.028″ (0.7 mm) diametercut wire shot (available from Pellets, Inc. 63 Industrial Drive, NorthTonawanda, N.Y., 14120). The column is immersed in a thermallycontrolled oil jacket, set initially to 160° C. The column is firstcooled ballistically to 125° C., then slow cooled to 20° C. at 0.04° C.per minute and held for one hour. Fresh TCB is introduced at about 65ml/min while the temperature is increased at 0.167° C. per minute.

Approximately 2000 ml portions of eluant from the preparative TREFcolumn are collected in a 16 station, heated fraction collector. Thepolymer is concentrated in each fraction using a rotary evaporator untilabout 50 to 100 ml of the polymer solution remains. The concentratedsolutions are allowed to stand overnight before adding excess methanol,filtering, and rinsing (approx. 300-500 ml of methanol including thefinal rinse). The filtration step is performed on a 3 position vacuumassisted filtering station using 5.0 μm polytetrafluoroethylene coatedfilter paper (available from Osmonics Inc., Cat# Z50WP04750). Thefiltrated fractions are dried overnight in a vacuum oven at 60° C. andweighed on an analytical balance before further testing.

Melt Strength

Melt Strength (MS) is measured by using a capillary rheometer fittedwith a 2.1 mm diameter, 20:1 die with an entrance angle of approximately45 degrees. After equilibrating the samples at 190° C. for 10 minutes,the piston is run at a speed of 1 inch/minute (2.54 cm/minute). Thestandard test temperature is 190° C. The sample is drawn uniaxially to aset of accelerating nips located 100 mm below the die with anacceleration of 2.4 mm/sec². The required tensile force is recorded as afunction of the take-up speed of the nip rolls. The maximum tensileforce attained during the test is defined as the melt strength. In thecase of polymer melt exhibiting draw resonance, the tensile force beforethe onset of draw resonance was taken as melt strength. The meltstrength is recorded in centiNewtons (“cN”).

Catalysts

The term “overnight”, if used, refers to a time of approximately 16-18hours, the term “room temperature”, refers to a temperature of 20-25°C., and the term “mixed alkanes” refers to a commercially obtainedmixture of C₆₋₉ aliphatic hydrocarbons available under the tradedesignation Isopar E®, from ExxonMobil Chemical Company. In the eventthe name of a compound herein does not conform to the structuralrepresentation thereof, the structural representation shall control. Thesynthesis of all metal complexes and the preparation of all screeningexperiments were carried out in a dry nitrogen atmosphere using dry boxtechniques. All solvents used were HPLC grade and were dried beforetheir use.

MMAO refers to modified methylalumoxane, a triisobutylaluminum modifiedmethylalumoxane available commercially from Akzo-Noble Corporation.

The preparation of catalyst (B1) is conducted as follows.

a) Preparation of(1-methylethyl)(2-hydroxy-3,5-di(t-butyl)phenyl)methylimine

3,5-Di-t-butylsalicylaldehyde (3.00 g) is added to 10 mL ofisopropylamine. The solution rapidly turns bright yellow. After stirringat ambient temperature for 3 hours, volatiles are removed under vacuumto yield a bright yellow, crystalline solid (97 percent yield).

b) Preparation of1,2-bis-(3,5-di-t-butylphenylene)(1-(N-(1-methylethyl)immino)methyl)(2-oxoyl)zirconiumdibenzyl

A solution of (1-methylethyl)(2-hydroxy-3,5-di(t-butyl)phenyl)imine (605mg, 2.2 mmol) in 5 mL toluene is slowly added to a solution ofZr(CH₂Ph)₄ (500 mg, 1.1 mmol) in 50 mL toluene. The resulting darkyellow solution is stirred for 30 min. Solvent is removed under reducedpressure to yield the desired product as a reddish-brown solid.

The preparation of catalyst (B2) is conducted as follows.

a) Preparation of(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)imine

2-Methylcyclohexylamine (8.44 mL, 64.0 mmol) is dissolved in methanol(90 mL), and di-t-butylsalicaldehyde (10.00 g, 42.67 mmol) is added. Thereaction mixture is stirred for three hours and then cooled to −25° C.for 12 hrs. The resulting yellow solid precipitate is collected byfiltration and washed with cold methanol (2×15 mL), and then dried underreduced pressure. The yield is 11.17 g of a yellow solid. ¹H NMR isconsistent with the desired product as a mixture of isomers.

b) Preparation ofbis-(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)immino)zirconium dibenzyl

A solution of(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)imine (7.63g, 23.2 mmol) in 200 mL toluene is slowly added to a solution ofZr(CH₂Ph)₄ (5.28 g, 11.6 mmol) in 600 mL toluene. The resulting darkyellow solution is stirred for 1 hour at 25° C. The solution is dilutedfurther with 680 mL toluene to give a solution having a concentration of0.00783 M.

Cocatalyst 1 A mixture of methyldi (C₁₄₋₁₈ alkyl)ammonium salts oftetrakis(pentafluorophenyl)borate (here-in-after armeenium borate),prepared by reaction of a long chain trialkylamine (Armeen™ M2HT,available from Akzo-Nobel, Inc.), HCl and Li[B(C₆F₅)₄], substantially asdisclosed in U.S. Pat. No. 5,919,9883, Ex. 2.

Cocatalyst 2 Mixed C₁₄₋₁₈ alkyldimethylammonium salt ofbis(tris(pentafluorophenyl)-alumane)-2-undecylimidazolide, preparedaccording to U.S. Pat. No. 6,395,671, Ex. 16.

Shuttling Agents The shuttling agents employed include diethylzinc (DEZ,SA1), di(i-butyl)zinc (SA2), di(n-hexyl)zinc (SA3), triethylaluminum(TEA, SA4), trioctylaluminum (SA5), triethylgallium (SA6),i-butylaluminum bis(dimethyl(t-butyl)siloxane) (SA7), i-butylaluminumbis(di(trimethylsilyl)amide) (SA8), n-octylaluminumdi(pyridine-2-methoxide) (SA9), bis(n-octadecyl)i-butylaluminum (SA10),i-butylaluminum bis(di(n-pentyl)amide) (SA11), n-octylaluminumbis(2,6-di-t-butylphenoxide) (SA12), n-octylaluminumdi(ethyl(1-naphthyl)amide) (SA13), ethylaluminumbis(t-butyldimethylsiloxide) (SA14), ethylaluminumdi(bis(trimethylsilyl)amide) (SA15), ethylaluminumbis(2,3,6,7-dibenzo-1-azacycloheptaneamide) (SA16), n-octylaluminumbis(2,3,6,7-dibenzo-1-azacycloheptaneamide) (SA17), n-octylaluminumbis(dimethyl(t-butyl)siloxide (SA18), ethylzinc (2,6-diphenylphenoxide)(SA19), and ethylzinc (t-butoxide) (SA20).

Examples 1-4 Comparative A-C

General High Throughput Parallel Polymerization Conditions

Polymerizations are conducted using a high throughput, parallelpolymerization reactor (PPR) available from Symyx technologies, Inc. andoperated substantially according to U.S. Pat. Nos. 6,248,540, 6,030,917,6,362,309, 6,306,658, and 6,316,663. Ethylene copolymerizations areconducted at 130° C. and 200 psi (1.4 MPa) with ethylene on demand using1.2 equivalents of cocatalyst 1 based on total catalyst used (1.1equivalents when MMAO is present). A series of polymerizations areconducted in a parallel pressure reactor (PPR) contained of 48individual reactor cells in a 6×8 array that are fitted with apre-weighed glass tube. The working volume in each reactor cell is 6000μL. Each cell is temperature and pressure controlled with stirringprovided by individual stirring paddles. The monomer gas and quench gasare plumbed directly into the PPR unit and controlled by automaticvalves. Liquid reagents are robotically added to each reactor cell bysyringes and the reservoir solvent is mixed alkanes. The order ofaddition is mixed alkanes solvent (4 ml), ethylene, 1-octene comonomer(1 ml), cocatalyst 1 or cocatalyst 1/MMAO mixture, shuttling agent, andcatalyst or catalyst mixture. When a mixture of cocatalyst 1 and MMAO ora mixture of two catalysts is used, the reagents are premixed in a smallvial immediately prior to addition to the reactor. When a reagent isomitted in an experiment, the above order of addition is otherwisemaintained. Polymerizations are conducted for approximately 1-2 minutes,until predetermined ethylene consumptions are reached. After quenchingwith CO, the reactors are cooled and the glass tubes are unloaded. Thetubes are transferred to a centrifuge/vacuum drying unit, and dried for12 hours at 60° C. The tubes containing dried polymer are weighed andthe difference between this weight and the tare weight gives the netyield of polymer. Results are contained in Table 1. In Table 1 andelsewhere in the application, comparative compounds are indicated by anasterisk (*).

Examples 1-4 demonstrate the synthesis of linear block copolymers by thepresent invention as evidenced by the formation of a very narrow MWD,essentially monomodal copolymer when DEZ is present and a bimodal, broadmolecular weight distribution product (a mixture of separately producedpolymers) in the absence of DEZ. Due to the fact that Catalyst (A1) isknown to incorporate more octene than Catalyst (B1), the differentblocks or segments of the resulting copolymers of the invention aredistinguishable based on branching or density.

TABLE 1 Cat. (A1) Cat (B1) Cocat MMAO shuttling Ex. (μmol) (μmol) (μmol)(μmol) agent (μmol) Yield (g) Mn Mw/Mn hexyls¹ A* 0.06 — 0.066 0.3 —0.1363 300502 3.32 — B* — 0.1 0.110 0.5 — 0.1581 36957 1.22 2.5 C* 0.060.1 0.176 0.8 — 0.2038 45526 5.30² 5.5 1 0.06 0.1 0.192 — DEZ (8.0)0.1974 28715 1.19 4.8 2 0.06 0.1 0.192 — DEZ (80.0) 0.1468 2161 1.1214.4 3 0.06 0.1 0.192 — TEA (8.0) 0.208 22675 1.71 4.6 4 0.06 0.1 0.192— TEA (80.0) 0.1879 3338 1.54 9.4 ¹C₆ or higher chain content per 1000carbons ²Bimodal molecular weight distribution

It may be seen the polymers produced according to the invention have arelatively narrow polydispersity (Mw/Mn) and larger block-copolymercontent (trimer, tetramer, or larger) than polymers prepared in theabsence of the shuttling agent.

Further characterizing data for the polymers of Table 1 are determinedby reference to the figures. More specifically DSC and ATREF resultsshow the following:

The DSC curve for the polymer of example 1 shows a 115.7° C. meltingpoint (Tm) with a heat of fusion of 158.1 J/g. The corresponding CRYSTAFcurve shows the tallest peak at 34.5° C. with a peak area of 52.9percent. The difference between the DSC Tm and the Tcrystaf is 81.2° C.

The DSC curve for the polymer of example 2 shows a peak with a 109.7° C.melting point (Tm) with a heat of fusion of 214.0 J/g. The correspondingCRYSTAF curve shows the tallest peak at 46.2° C. with a peak area of57.0 percent. The difference between the DSC Tm and the Tcrystaf is63.5° C.

The DSC curve for the polymer of example 3 shows a peak with a 120.7° C.melting point (Tm) with a heat of fusion of 160.1 J/g. The correspondingCRYSTAF curve shows the tallest peak at 66.1° C. with a peak area of71.8 percent. The difference between the DSC Tm and the Tcrystaf is54.6° C.

The DSC curve for the polymer of example 4 shows a peak with a 104.5° C.melting point (Tm) with a heat of fusion of 170.7 J/g. The correspondingCRYSTAF curve shows the tallest peak at 30° C. with a peak area of 18.2percent. The difference between the DSC Tm and the Tcrystaf is 74.5° C.

The DSC curve for comparative A shows a 90.0° C. melting point (Tm) witha heat of fusion of 86.7 J/g. The corresponding CRYSTAF curve shows thetallest peak at 48.5° C. with a peak area of 29.4 percent. Both of thesevalues are consistent with a resin that is low in density. Thedifference between the DSC Tm and the Tcrystaf is 41.8° C.

The DSC curve for comparative B shows a 129.8° C. melting point (Tm)with a heat of fusion of 237.0 J/g. The corresponding CRYSTAF curveshows the tallest peak at 82.4° C. with a peak area of 83.7 percent.Both of these values are consistent with a resin that is high indensity. The difference between the DSC Tm and the Tcrystaf is 47.4° C.

The DSC curve for comparative C shows a 125.3° C. melting point (Tm)with a heat of fusion of 143.0 J/g. The corresponding CRYSTAF curveshows the tallest peak at 81.8° C. with a peak area of 34.7 percent aswell as a lower crystalline peak at 52.4° C. The separation between thetwo peaks is consistent with the presence of a high crystalline and alow crystalline polymer. The difference between the DSC Tm and theTcrystaf is 43.5° C.

Examples 5-19 Comparatives D-F, Continuous Solution Polymerization,Catalyst A1/B2+DEZ

Continuous solution polymerizations are carried out in a computercontrolled autoclave reactor equipped with an internal stirrer. Purifiedmixed alkanes solvent (Isopar™ E available from ExxonMobil ChemicalCompany), ethylene at 2.70 lbs/hour (1.22 kg/hour), 1-octene, andhydrogen (where used) are supplied to a 3.8 L reactor equipped with ajacket for temperature control and an internal thermocouple. The solventfeed to the reactor is measured by a mass-flow controller. A variablespeed diaphragm pump controls the solvent flow rate and pressure to thereactor. At the discharge of the pump, a side stream is taken to provideflush flows for the catalyst and cocatalyst 1 injection lines and thereactor agitator. These flows are measured by Micro-Motion mass flowmeters and controlled by control valves or by the manual adjustment ofneedle valves. The remaining solvent is combined with 1-octene,ethylene, and hydrogen (where used) and fed to the reactor. A mass flowcontroller is used to deliver hydrogen to the reactor as needed. Thetemperature of the solvent/monomer solution is controlled by use of aheat exchanger before entering the reactor. This stream enters thebottom of the reactor. The catalyst component solutions are meteredusing pumps and mass flow meters and are combined with the catalystflush solvent and introduced into the bottom of the reactor. The reactoris run liquid-full at 500 psig (3.45 MPa) with vigorous stirring.Product is removed through exit lines at the top of the reactor. Allexit lines from the reactor are steam traced and insulated.Polymerization is stopped by the addition of a small amount of waterinto the exit line along with any stabilizers or other additives andpassing the mixture through a static mixer. The product stream is thenheated by passing through a heat exchanger before devolatilization. Thepolymer product is recovered by extrusion using a devolatilizingextruder and water cooled pelletizer. Process details and results arecontained in Table 2. Selected polymer properties are provided in Table3.

TABLE 2 Process details for preparation of exemplary polymers Cat Cat AlCat B2 DEZ Cocat Cocat Poly C₈H₁₆ Solv. H₂ T Al² Flow B2³ Flow DEZ FlowConc. Flow [C₂H₄]/ Rate⁵ Ex. kg/hr kg/hr sccm¹ ° C. ppm kg/hr ppm kg/hrConc % kg/hr ppm kg/hr [DEZ]⁴ kg/hr Conv %⁶ Solids % Eff.⁷ D* 1.63 12.729.90 120 142.2  0.14 — — 0.19 0.32  820 0.17 536 1.81 88.8 11.2 95.2 E*″  9.5 5.00 ″ — — 109 0.10 0.19 ″ 1743 0.40 485 1.47 89.9 11.3 126.8 F*″ 11.3 251.6 ″ 71.7 0.06 30.8 0.06 — — ″ 0.11 — 1.55 88.5 10.3 257.7  5″ ″ — ″ ″ 0.14 30.8 0.13 0.17 0.43 ″ 0.26 419 1.64 89.6 11.1 118.3  6 ″″ 4.92 ″ ″ 0.10 30.4 0.08 0.17 0.32 ″ 0.18 570 1.65 89.3 11.1 172.7  7 ″″ 21.70 ″ ″ 0.07 30.8 0.06 0.17 0.25 ″ 0.13 718 1.60 89.2 10.6 244.1  8″ ″ 36.90 ″ ″ 0.06 ″ ″ ″ 0.10 ″ 0.12 1778  1.62 90.0 10.8 261.1  9 ″ ″78.43 ″ ″ ″ ″ ″ ″ 0.04 ″ ″ 4596  1.63 90.2 10.8 267.9 10 ″ ″ 0.00 12371.1 0.12 30.3 0.14 0.34 0.19 1743 0.08 415 1.67 90.31 11.1 131.1 11 ″ ″″ 120 71.1 0.16 ″ 0.17 0.80 0.15 1743 0.10 249 1.68 89.56 11.1 100.6 12″ ″ ″ 121 71.1 0.15 ″ 0.07 ″ 0.09 1743 0.07 396 1.70 90.02 11.3 137.0 13″ ″ ″ 122 71.1 0.12 ″ 0.06 ″ 0.05 1743 0.05 653 1.69 89.64 11.2 161.9 14″ ″ ″ 120 71.1 0.05 ″ 0.29 ″ 0.10 1743 0.10 395 1.41 89.42 9.3 114.1 152.45 ″ ″ ″ 71.1 0.14 ″ 0.17 ″ 0.14 1743 0.09 282 1.80 89.33 11.3 121.316 ″ ″ ″ 122 71.1 0.10 ″ 0.13 ″ 0.07 1743 0.07 485 1.78 90.11 11.2 159.717 ″ ″ ″ 121 71.1 0.10 ″ 0.14 ″ 0.08 1743 ″ 506 1.75 89.08 11.0 155.6 180.69 ″ ″ 121 71.1 ″ ″ 0.22 ″ 0.11 1743 0.10 331 1.25 89.93 8.8 90.2 190.32 ″ ″ 122 71.1 0.06 ″ ″ ″ 0.09 1743 0.08 367 1.16 90.74 8.4 106.0*Comparative, not an example of the invention ¹standard cm³/min²[N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafniumdimethyl³bis-(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)immino)zirconium dibenzyl ⁴molar ratio in reactor ⁵polymer production rate⁶percent ethylene conversion in reactor ⁷efficiency, kg polymer/g Mwhere g M = g Hf + g Zr

TABLE 3 Properties of exemplary polymers Heat of CRYSTAF Density Mw MnFusion T_(m) T_(c) T_(CRYSTAF) Tm − T_(CRYSTAF) Peak Area Ex. (g/cm³) I₂I₁₀ I₁₀/I₂ (g/mol) (g/mol) Mw/Mn (J/g) (° C.) (° C.) (° C.) (° C.)(percent) D* 0.8627 1.5 10.0 6.5 110,000 55,800 2.0 32 37 45 30 7 99 E*0.9378 7.0 39.0 5.6 65,000 33,300 2.0 183 124 113 79 45 95 F* 0.8895 0.912.5 13.4 137,300 9,980 13.8 90 125 111 78 47 20  5 0.8786 1.5 9.8 6.7104,600 53,200 2.0 55 120 101 48 72 60  6 0.8785 1.1 7.5 6.5 10960053300 2.1 55 115 94 44 71 63  7 0.8825 1.0 7.2 7.1 118,500 53,100 2.2 69121 103 49 72 29  8 0.8828 0.9 6.8 7.7 129,000 40,100 3.2 68 124 106 8043 13  9 0.8836 1.1 9.7 9.1 129600 28700 4.5 74 125 109 81 44 16 100.8784 1.2 7.5 6.5 113,100 58,200 1.9 54 116 92 41 75 52 11 0.8818 9.159.2 6.5 66,200 36,500 1.8 63 114 93 40 74 25 12 0.8700 2.1 13.2 6.4101,500 55,100 1.8 40 113 80 30 83 91 13 0.8718 0.7 4.4 6.5 132,10063,600 2.1 42 114 80 30 81 8 14 0.9116 2.6 15.6 6.0 81,900 43,600 1.9123 121 106 73 48 92 15 0.8719 6.0 41.6 6.9 79,900 40,100 2.0 33 114 9132 82 10 16 0.8758 0.5 3.4 7.1 148,500 74,900 2.0 43 117 96 48 69 65 170.8757 1.7 11.3 6.8 107,500 54,000 2.0 43 116 96 43 73 57 18 0.9192 4.124.9 6.1 72,000 37,900 1.9 136 120 106 70 50 94 19 0.9344 3.4 20.3 6.076,800 39,400 1.9 169 125 112 80 45 88

The resulting polymers are tested by DSC and ATREF as with previousexamples. Results are as follows:

The DSC curve for the polymer of example 5 shows a peak with a 119.6° C.melting point (Tm) with a heat of fusion of 60.0 J/g. The correspondingCRYSTAF curve shows the tallest peak at 47.6° C. with a peak area of59.5 percent. The delta between the DSC Tm and the Tcrystaf is 72.0° C.

The DSC curve for the polymer of example 6 shows a peak with a 115.2° C.melting point (Tm) with a heat of fusion of 60.4 J/g. The correspondingCRYSTAF curve shows the tallest peak at 44.2° C. with a peak area of62.7 percent. The delta between the DSC Tm and the Tcrystaf is 71.0° C.

The DSC curve for the polymer of example 7 shows a peak with a 121.3° C.melting point with a heat of fusion of 69.1 J/g. The correspondingCRYSTAF curve shows the tallest peak at 49.2° C. with a peak area of29.4 percent. The delta between the DSC Tm and the Tcrystaf is 72.1° C.

The DSC curve for the polymer of example 8 shows a peak with a 123.5° C.melting point (Tm) with a heat of fusion of 67.9 J/g. The correspondingCRYSTAF curve shows the tallest peak at 80.1° C. with a peak area of12.7 percent. The delta between the DSC Tm and the Tcrystaf is 43.4° C.

The DSC curve for the polymer of example 9 shows a peak with a 124.6° C.melting point (Tm) with a heat of fusion of 73.5 J/g. The correspondingCRYSTAF curve shows the tallest peak at 80.8° C. with a peak area of16.0 percent. The delta between the DSC Tm and the Tcrystaf is 43.8° C.

The DSC curve for the polymer of example 10 shows a peak with a 115.6°C. melting point (Tm) with a heat of fusion of 60.7 J/g. Thecorresponding CRYSTAF curve shows the tallest peak at 40.9° C. with apeak area of 52.4 percent. The delta between the DSC Tm and the Tcrystafis 74.7° C.

The DSC curve for the polymer of example 11 shows a peak with a 113.6°C. melting point (Tm) with a heat of fusion of 70.4 J/g. Thecorresponding CRYSTAF curve shows the tallest peak at 39.6° C. with apeak area of 25.2 percent. The delta between the DSC Tm and the Tcrystafis 74.1° C.

The DSC curve for the polymer of example 12 shows a peak with a 113.2°C. melting point (Tm) with a heat of fusion of 48.9 J/g. Thecorresponding CRYSTAF curve shows no peak equal to or above 30° C.(Tcrystaf for purposes of further calculation is therefore set at 30°C.). The delta between the DSC Tm and the Tcrystaf is 83.2° C.

The DSC curve for the polymer of example 13 shows a peak with a 114.4°C. melting point (Tm) with a heat of fusion of 49.4 J/g. Thecorresponding CRYSTAF curve shows the tallest peak at 33.8° C. with apeak area of 7.7 percent. The delta between the DSC Tm and the Tcrystafis 84.4° C.

The DSC for the polymer of example 14 shows a peak with a 120.8° C.melting point (Tm) with a heat of fusion of 127.9 J/g. The correspondingCRYSTAF curve shows the tallest peak at 72.9° C. with a peak area of92.2 percent. The delta between the DSC Tm and the Tcrystaf is 47.9° C.

The DSC curve for the polymer of example 15 shows a peak with a 114.3°C. melting point (Tm) with a heat of fusion of 36.2 J/g. Thecorresponding CRYSTAF curve shows the tallest peak at 32.3° C. with apeak area of 9.8 percent. The delta between the DSC Tm and the Tcrystafis 82.0° C.

The DSC curve for the polymer of example 16 shows a peak with a 116.6°C. melting point (Tm) with a heat of fusion of 44.9 J/g. Thecorresponding CRYSTAF curve shows the tallest peak at 48.0° C. with apeak area of 65.0 percent. The delta between the DSC Tm and the Tcrystafis 68.6° C.

The DSC curve for the polymer of example 17 shows a peak with a 116.0°C. melting point (Tm) with a heat of fusion of 47.0 J/g. Thecorresponding CRYSTAF curve shows the tallest peak at 43.1° C. with apeak area of 56.8 percent. The delta between the DSC Tm and the Tcrystafis 72.9° C.

The DSC curve for the polymer of example 18 shows a peak with a 120.5°C. melting point (Tm) with a heat of fusion of 141.8 J/g. Thecorresponding CRYSTAF curve shows the tallest peak at 70.0° C. with apeak area of 94.0 percent. The delta between the DSC Tm and the Tcrystafis 50.5° C.

The DSC curve for the polymer of example 19 shows a peak with a 124.8°C. melting point (Tm) with a heat of fusion of 174.8 J/g. Thecorresponding CRYSTAF curve shows the tallest peak at 79.9° C. with apeak area of 87.9 percent. The delta between the DSC Tm and the Tcrystafis 45.0° C.

The DSC curve for the polymer of comparative D shows a peak with a 37.3°C. melting point (Tm) with a heat of fusion of 31.6 J/g. Thecorresponding CRYSTAF curve shows no peak equal to and above 30° C. Bothof these values are consistent with a resin that is low in density. Thedelta between the DSC Tm and the Tcrystaf is 7.3° C.

The DSC curve for the polymer of comparative E shows a peak with a124.0° C. melting point (Tm) with a heat of fusion of 179.3 J/g. Thecorresponding CRYSTAF curve shows the tallest peak at 79.3° C. with apeak area of 94.6 percent. Both of these values are consistent with aresin that is high in density. The delta between the DSC Tm and theTcrystaf is 44.6° C.

The DSC curve for the polymer of comparative F shows a peak with a124.8° C. melting point (Tm) with a heat of fusion of 90.4 J/g. Thecorresponding CRYSTAF curve shows the tallest peak at 77.6° C. with apeak area of 19.5 percent. The separation between the two peaks isconsistent with the presence of both a high crystalline and a lowcrystalline polymer. The delta between the DSC Tm and the Tcrystaf is47.2° C.

Physical Property Testing

Polymer samples are evaluated for physical properties such as hightemperature resistance properties, as evidenced by TMA temperaturetesting, pellet blocking strength, high temperature recovery, hightemperature compression set and storage modulus ratio, G′(25°C.)/G′(100° C.). Several commercially available polymers are included inthe tests: Comparative G* is a substantially linear ethylene/1-octenecopolymer (AFFINITY®, available from The Dow Chemical Company),Comparative H* is an elastomeric, substantially linear ethylene/1-octenecopolymer (AFFINITY®EG8100, available from The Dow Chemical Company),Comparative I is a substantially linear ethylene/1-octene copolymer(AFFINITY®PL1840, available from The Dow Chemical Company), ComparativeJ is a hydrogenated styrene/butadiene/styrene triblock copolymer(KRATON™ G1652, available from KRATON Polymers), Comparative K is athermoplastic vulcanizate (TPV, a polyolefin blend containing dispersedtherein a crosslinked elastomer). Results are presented in Table 4.

TABLE 4 High Temperature Mechanical Properties TMA-1 mm Pellet Blocking300% Strain Compression penetration Strength G′(25° C.)/ Recovery (80°C.) Set (70° C.) Ex. (° C.) lb/ft² (kPa) G′(100° C.) (percent) (percent)D* 51 — 9 Failed — E* 130 — 18 — — F* 70 141 (6.8) 9 Failed 100  5 104 0 (0) 6 81 49  6 110 — 5 — 52  7 113 — 4 84 43  8 111 — 4 Failed 41  997 — 4 — 66 10 108 — 5 81 55 11 100 — 8 — 68 12 88 — 8 — 79 13 95 — 6 8471 14 125 — 7 — — 15 96 — 5 — 58 16 113 — 4 — 42 17 108  0 (0) 4 82 4718 125 — 10 — — 19 133 — 9 — — G* 75 463 (22.2) 89 Failed 100 H* 70 213(10.2) 29 Failed 100 I* 111 — 11 — — J* 107 — 5 Failed 100 K* 152 — 3 —40

In Table 4, Comparative F (which is a physical blend of the two polymersresulting from simultaneous polymerizations using catalyst A1 and B1)has a 1 mm penetration temperature of about 70° C., while Examples 5-9have a 1 mm penetration temperature of 100° C. or greater. Further,examples 10-19 all have a 1 mm penetration temperature of greater than85° C., with most having 1 mm TMA temperature of greater than 90° C. oreven greater than 100° C. This shows that the novel polymers have betterdimensional stability at higher temperatures compared to a physicalblend. Comparative J (a commercial SEBS) has a good 1 mm TMA temperatureof about 107° C., but it has very poor (high temperature 70° C.)compression set of about 100 percent and it also failed to recover(sample broke) during a high temperature (80° C.) 300 percent strainrecovery. Thus the exemplified polymers have a unique combination ofproperties unavailable even in some commercially available, highperformance thermoplastic elastomers.

Similarly, Table 4 shows a low (good) storage modulus ratio, G′(25°C.)/G′(100° C.), for the inventive polymers of 6 or less, whereas aphysical blend (Comparative F) has a storage modulus ratio of 9 and arandom ethylene/octene copolymer (Comparative G) of similar density hasa storage modulus ratio an order of magnitude greater (89). It isdesirable that the storage modulus ratio of a polymer be as close to 1as possible. Such polymers will be relatively unaffected by temperature,and fabricated articles made from such polymers can be usefully employedover a broad temperature range. This feature of low storage modulusratio and temperature independence is particularly useful in elastomerapplications such as in pressure sensitive adhesive formulations.

The data in Table 4 also demonstrate that the polymers of the inventionpossess improved pellet blocking strength. In particular, Example 5 hasa pellet blocking strength of 0 MPa, meaning it is free flowing underthe conditions tested, compared to Comparatives F and G which showconsiderable blocking. Blocking strength is important since bulkshipment of polymers having large blocking strengths can result inproduct clumping or sticking together upon storage or shipping,resulting in poor handling properties.

High temperature (70° C.) compression set for the inventive polymers isgenerally good, meaning generally less than about 80 percent, preferablyless than about 70 percent and especially less than about 60 percent. Incontrast, Comparatives F, G, H and J all have a 70° C. compression setof 100 percent (the maximum possible value, indicating no recovery).Good high temperature compression set (low numerical values) isespecially needed for applications such as gaskets, window profiles,o-rings, and the like.

TABLE 5 Ambient Temperature Mechanical Properties Tensile 100% 300%Retractive Stress Abrasion: Notched Strain Strain Stress at Compres-Relax- Flex Tensile Tensile Elongation Tensile Elongation Volume TearRecovery Recovery 150% sion ation Modulus Modulus Strength at Break¹Strength at Break Loss Strength 21° C. 21° C. Strain Set 21° C. at 50%Ex. (MPa) (MPa) (MPa)¹ (%) (MPa) (%) (mm³) (mJ) (percent) (percent)(kPa) (Percent) Strain² D* 12 5 — — 10 1074 — — 91 83 760 — — E* 895 589— 31 1029 — — — — — — — F* 57 46 — — 12 824 93 339 78 65 400 42 —  5 3024 14 951 16 1116 48 — 87 74 790 14 33  6 33 29 — — 14 938 — — — 75 86113 —  7 44 37 15 846 14 854 39 — 82 73 810 20 —  8 41 35 13 785 14 81045 461 82 74 760 22 —  9 43 38 — — 12 823 — — — — — 25 — 10 23 23 — — 14902 — — 86 75 860 12 — 11 30 26 — — 16 1090 — 976 89 66 510 14 30 12 2017 12 961 13 931 — 1247  91 75 700 17 — 13 16 14 — — 13 814 — 691 91 — —21 — 14 212 160 — — 29 857 — — — — — — — 15 18 14 12 1127  10 1573 —2074  89 83 770 14 — 16 23 20 — — 12 968 — — 88 83 1040  13 — 17 20 18 —— 13 1252 — 1274  13 83 920  4 — 18 323 239 — — 30 808 — — — — — — — 19706 483 — — 36 871 — — — — — — — G* 15 15 — — 17 1000 — 746 86 53 110 2750 H* 16 15 — — 15 829 — 569 87 60 380 23 — I* 210 147 — — 29 697 — — —— — — — J* — — — — 32 609 — — 93 96 1900  25 — K* — — — — — — — — — — —30 — ¹Tested at 51 cm/minute ²measured at 38° C. for 12 hours

Table 5 shows results for mechanical properties for the new polymers aswell as for various comparison polymers at ambient temperatures. It maybe seen that the inventive polymers have very good abrasion resistancewhen tested according to ISO 4649, generally showing a volume loss ofless than about 90 mm³, preferably less than about 80 mm³, andespecially less than about 50 mm³. In this test, higher numbers indicatehigher volume loss and consequently lower abrasion resistance.

Tear strength as measured by tensile notched tear strength of theinventive polymers is generally 1000 mJ or higher, as shown in Table 5.Tear strength for the inventive polymers can be as high as 3000 mJ, oreven as high as 5000 mJ. Comparative polymers generally have tearstrengths no higher than 750 mJ.

Table 5 also shows that the polymers of the invention have betterretractive stress at 150 percent strain (demonstrated by higherretractive stress values) than some of the comparative samples.Comparative Examples F, G and H have retractive stress value at 150percent strain of 400 kPa or less, while the inventive polymers haveretractive stress values at 150 percent strain of 500 kPa (Ex. 11) to ashigh as about 1100 kPa (Ex. 17). Polymers having higher than 150 percentretractive stress values would be quite useful for elastic applications,such as elastic fibers and fabrics, especially nonwoven fabrics. Otherapplications include diaper, hygiene, and medical garment waistbandapplications, such as tabs and elastic bands.

Table 5 also shows that stress relaxation (at 50 percent strain) is alsoimproved (less) for the inventive polymers as compared to, for example,Comparative G. Lower stress relaxation means that the polymer retainsits force better in applications such as diapers and other garmentswhere retention of elastic properties over long time periods at bodytemperatures is desired.

Optical Testing

TABLE 6 Polymer Optical Properties Ex. Internal Haze (percent) Clarity(percent) 45° Gloss (percent) F* 84 22 49 G* 5 73 56  5 13 72 60  6 3369 53  7 28 57 59  8 20 65 62  9 61 38 49 10 15 73 67 11 13 69 67 12 875 72 13 7 74 69 14 59 15 62 15 11 74 66 16 39 70 65 17 29 73 66 18 6122 60 19 74 11 52 G* 5 73 56 H* 12 76 59 I* 20 75 59

The optical properties reported in Table 6 are based on compressionmolded films substantially lacking in orientation. Optical properties ofthe polymers may be varied over wide ranges, due to variation incrystallite size, resulting from variation in the quantity of chainshuttling agent employed in the polymerization.

Extractions of Multi-Block Copolymers

Extraction studies of the polymers of examples 5, 7 and Comparative Eare conducted. In the experiments, the polymer sample is weighed into aglass fritted extraction thimble and fitted into a Kumagawa typeextractor. The extractor with sample is purged with nitrogen, and a 500mL round bottom flask is charged with 350 mL of diethyl ether. The flaskis then fitted to the extractor. The ether is heated while beingstirred. Time is noted when the ether begins to condense into thethimble, and the extraction is allowed to proceed under nitrogen for 24hours. At this time, heating is stopped and the solution is allowed tocool. Any ether remaining in the extractor is returned to the flask. Theether in the flask is evaporated under vacuum at ambient temperature,and the resulting solids are purged dry with nitrogen. Any residue istransferred to a weighed bottle using successive washes of hexane. Thecombined hexane washes are then evaporated with another nitrogen purge,and the residue dried under vacuum overnight at 40° C. Any remainingether in the extractor is purged dry with nitrogen.

A second clean round bottom flask charged with 350 mL of hexane is thenconnected to the extractor. The hexane is heated to reflux with stirringand maintained at reflux for 24 hours after hexane is first noticedcondensing into the thimble. Heating is then stopped and the flask isallowed to cool. Any hexane remaining in the extractor is transferredback to the flask. The hexane is removed by evaporation under vacuum atambient temperature, and any residue remaining in the flask istransferred to a weighed bottle using successive hexane washes. Thehexane in the flask is evaporated by a nitrogen purge, and the residueis vacuum dried overnight at 40° C.

The polymer sample remaining in the thimble after the extractions istransferred from the thimble to a weighed bottle and vacuum driedovernight at 40° C. Results are contained in Table 7.

TABLE 7 ether ether C₈ hexane hexane C₈ residue wt. soluble soluble molesoluble soluble mole C₈ mole Sample (g) (g) (percent) percent¹ (g)(percent) percent¹ percent¹ Comp. 1.097 0.063 5.69 12.2 0.245 22.35 13.66.5 F* Ex. 5 1.006 0.041 4.08 — 0.040 3.98 14.2 11.6 Ex. 7 1.092 0.0171.59 13.3 0.012 1.10 11.7 9.9 ¹Determined by ¹³C NMR

Additional Polymer Examples 19A-J Continuous Solution Polymerization,Catalyst A1/B2+DEZ

For Examples 19A-I

Continuous solution polymerizations are carried out in a computercontrolled well-mixed reactor. Purified mixed alkanes solvent (Isopar™ Eavailable from Exxon Mobil, Inc.), ethylene, 1-octene, and hydrogen(where used) are combined and fed to a 27 gallon reactor. The feeds tothe reactor are measured by mass-flow controllers. The temperature ofthe feed stream is controlled by use of a glycol cooled heat exchangerbefore entering the reactor. The catalyst component solutions aremetered using pumps and mass flow meters. The reactor is run liquid-fullat approximately 550 psig pressure. Upon exiting the reactor, water andadditive are injected in the polymer solution. The water hydrolyzes thecatalysts, and terminates the polymerization reactions. The post reactorsolution is then heated in preparation for a two-stage devolatization.The solvent and unreacted monomers are removed during the devolatizationprocess. The polymer melt is pumped to a die for underwater pelletcutting.

For Example 19J

Continuous solution polymerizations are carried out in a computercontrolled autoclave reactor equipped with an internal stirrer. Purifiedmixed alkanes solvent (Isopar™ E available from ExxonMobil ChemicalCompany), ethylene at 2.70 lbs/hour (1.22 kg/hour), 1-octene, andhydrogen (where used) are supplied to a 3.8 L reactor equipped with ajacket for temperature control and an internal thermocouple. The solventfeed to the reactor is measured by a mass-flow controller. A variablespeed diaphragm pump controls the solvent flow rate and pressure to thereactor. At the discharge of the pump, a side stream is taken to provideflush flows for the catalyst and cocatalyst injection lines and thereactor agitator. These flows are measured by Micro-Motion mass flowmeters and controlled by control valves or by the manual adjustment ofneedle valves. The remaining solvent is combined with 1-octene,ethylene, and hydrogen (where used) and fed to the reactor. A mass flowcontroller is used to deliver hydrogen to the reactor as needed. Thetemperature of the solvent/monomer solution is controlled by use of aheat exchanger before entering the reactor. This stream enters thebottom of the reactor. The catalyst component solutions are meteredusing pumps and mass flow meters and are combined with the catalystflush solvent and introduced into the bottom of the reactor. The reactoris run liquid-full at 500 psig (3.45 MPa) with vigorous stirring.Product is removed through exit lines at the top of the reactor. Allexit lines from the reactor are steam traced and insulated.Polymerization is stopped by the addition of a small amount of waterinto the exit line along with any stabilizers or other additives andpassing the mixture through a static mixer. The product stream is thenheated by passing through a heat exchanger before devolatilization. Thepolymer product is recovered by extrusion using a devolatilizingextruder and water cooled pelletizer.

Process details and results are contained in Table 8. Selected polymerproperties are provided in Tables 9A-C.

In Table 9B, inventive examples 19F and 19G show low immediate set ofaround 65-70% strain after 500% elongation.

TABLE 8 Polymerization Conditions Cat Cat Cat A1² Cat A1 B2³ B2 DEZ DEZCocat 1 C₂H₄ C₈H₁₆ Solv. H₂ T Conc. Flow Conc. Flow Conc Flow Conc. Ex.lb/hr lb/hr lb/hr sccm¹ ° C. ppm lb/hr ppm lb/hr wt % lb/hr ppm 19A55.29 32.03 323.03 101 120 600 0.25 200 0.42 3.0 0.70 4500 19B 53.9528.96 325.3 577 120 600 0.25 200 0.55 3.0 0.24 4500 19C 55.53 30.97324.37 550 120 600 0.216 200 0.609 3.0 0.69 4500 19D 54.83 30.58 326.3360 120 600 0.22 200 0.63 3.0 1.39 4500 19E 54.95 31.73 326.75 251 120600 0.21 200 0.61 3.0 1.04 4500 19F 50.43 34.80 330.33 124 120 600 0.20200 0.60 3.0 0.74 4500 19G 50.25 33.08 325.61 188 120 600 0.19 200 0.593.0 0.54 4500 19H 50.15 34.87 318.17 58 120 600 0.21 200 0.66 3.0 0.704500 19I 55.02 34.02 323.59 53 120 600 0.44 200 0.74 3.0 1.72 4500 19J7.46 9.04 50.6 47 120 150 0.22 76.7 0.36 0.5 0.19 — Zn⁴ Cocat 1 Cocat 2Cocat 2 in Poly Flow Conc. Flow polymer Rate⁵ Conv⁶ Polymer Ex. lb/hrppm lb/hr ppm lb/hr wt % wt % Eff.⁷ 19A 0.65 525 0.33 248 83.94 88.017.28 297 19B 0.63 525 0.11 90 80.72 88.1 17.2 295 19C 0.61 525 0.33 24684.13 88.9 17.16 293 19D 0.66 525 0.66 491 82.56 88.1 17.07 280 19E 0.64525 0.49 368 84.11 88.4 17.43 288 19F 0.52 525 0.35 257 85.31 87.5 17.09319 19G 0.51 525 0.16 194 83.72 87.5 17.34 333 19H 0.52 525 0.70 25983.21 88.0 17.46 312 19I 0.70 525 1.65 600 86.63 88.0 17.6 275 19J — — —— — — — — ¹standard cm³/min²[N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafniumdimethyl³bis-(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)immino)zirconium dimethyl ⁴ppm in final product calculated by mass balance⁵polymer production rate ⁶weight percent ethylene conversion in reactor⁷efficiency, kg polymer/g M where g M = g Hf + g Z

TABLE 9A Polymer Physical Properties Den- Mw Mn Heat of CRYSTAF sity (g/(g/ Mw/ Fusion TCRYSTAF Tm − TCRYSTAF Peak Area Ex. (g/cc) I2 I10 I10/I2mol) mol) Mn (J/g) Tm (° C.) Tc (° C.) (° C.) (° C.) (wt %) 19A 0.87810.9 6.4 6.9 123700 61000 2.0 56 119 97 46 73 40 19B 0.8749 0.9 7.3 7.8133000 44300 3.0 52 122 100 30 92 76 19C 0.8753 5.6 38.5 6.9 81700 373002.2 46 122 100 30 92 8 19D 0.8770 4.7 31.5 6.7 80700 39700 2.0 52 119 9748 72 5 19E 0.8750 4.9 33.5 6.8 81800 41700 2.0 49 121 97 36 84 12 19F0.8652 1.1 7.5 6.8 124900 60700 2.1 27 119 88 30 89 89 19G 0.8649 0.96.4 7.1 135000 64800 2.1 26 120 92 30 90 90 19H 0.8654 1.0 7.0 7.1131600 66900 2.0 26 118 88 — — — 19I 0.8774 11.2 75.2 6.7 66400 337002.0 49 119 99 40 79 13 19J 0.8995 5.6 39.4 7.0 75500 29900 2.5 101 122106 — — —

TABLE 9B Polymer Physical Properties of Compression Molded FilmImmediate Immediate Immediate Set after Set after Set after RecoveryRecovery Recovery Density Melt Index 100% Strain 300% Strain 500% Strainafter 100% after 300% after 500% Example (g/cm³) (g/10 min) (%) (%) (%)(%) (%) (%) 19A 0.878 0.9 15 63 131 85 79 74 19B 0.877 0.88 14 49 97 8684 81 19F 0.865 1 — — 70 — 87 86 19G 0.865 0.9 — — 66 — — 87 19H 0.8650.92 — 39 — — 87 —

TABLE 9C Average Block Index For exemplary polymers¹ Example Zn/C₂ ²Average BI Polymer F 0 0 Polymer 8 0.56 0.59 Polymer 19a 1.3 0.62Polymer 5 2.4 0.52 Polymer 19b 0.56 0.54 Polymer 19h 3.15 0.59¹Additional information regarding the calculation of the block indicesfor various polymers is disclosed in U.S. patent application Ser. No.     (insert when known, entitled “Ethylene/α-Olefin BlockInterpolymers”, filed on Mar. 15, 2006, in the name of Colin L. P. Shan,Lonnie Hazlitt, et. al. and assigned to Dow Global Technologies Inc.,the disclose of which is incorporated by reference herein in itsentirety. ²Zn/C₂*1000 = (Zn feed flow*Zn concentration/1000000/Mw ofZn)/(Total Ethylene feed flow*(1-fractional ethylene conversion rate)/Mwof Ethylene)*1000. Please note that “Zn” in “Zn/C₂*1000” refers to theamount of zinc in diethyl zinc (“DEZ”) used in the polymerizationprocess, and “C2”refers to the amount of ethylene used in thepolymerization process.Impact Modified Compositions

The specific ethylene/α-olefin multi-block interpolymer and the amountemployed as the impact modifier will vary depending, among othervariables, upon the polymer to be impact modified, the application, andthe desired properties. It has been found that if improved lowtemperature impact is desired then an ethylene/α-olefin multi-blockinterpolymer prepared using relatively more chain shuttling agent may bemore useful. While any amount of shuttling agent may be useful, it isoften preferable to prepare the interpolymer using from about 50 toabout 300 ppm chain shuttling agent. While not wishing to be bound toany particular theory it is believed that this is often results in anadvantageous multi-core shell morphology as described in, for example,PCT Application No. PCT/US2005/008917, filed on Mar. 17, 2005, whichclaims priority to U.S. Provisional Application No. 60/553,906, filedMar. 17, 2004. For purposes of United States patent practice, thecontents of said provisional and PCT application are herein incorporatedby reference in their entirety.

It has also been found that to a certain extent the tougheningefficiency (the amount of improvement expected from a minimal amount ofimpact modifier) is improved as the density of the ethylene/α-olefinmulti-block interpolymer is decreased. For this reason it is oftendesirable to employ an interpolymer with a density of from about 0.85 toabout 0.93 g/cc.

The amount of ethylene/α-olefin multi-block interpolymer employed willvary depending, among other variables, upon the polymer to be impactmodified, the application, and the desired properties. Typically, animpact-modifying amount is employed to maintain or increase the notchedIzod impact strength at 20° C. at least about 5%, preferably at leastabout 10%, more preferably at least about 15% over a similar compositionlacking ethylene/α-olefin multi-block interpolymer. If one also desireslow temperature impact properties then one may employ an amountsufficient to maintain or increase the notched Izod impact strength at−20° C. at least about 5%, preferably at least about 10%, morepreferably at least about 15% over a similar composition lackingethylene/α-olefin multi-block interpolymer. This amount may be the sameor different than the amount employed to maintain or increase thenotched Izod impact strength at 20° C.

The amounts of ingredients employed will differ depending, among otherthings, on the desired properties and application. Often, the weightratio of multi-block copolymer to polyolefin may be from about 49:51 toabout 5:95, more preferably from 35:65 to about 10:90. Preferably, it isdesirable to employ at least about 1, preferably at least about 5, morepreferably at least about 10, even more preferably at least about 20weight percent of the ethylene/α-olefin multi-block interpolymer orblend as an impact modifier. Similarly, it is desirable to employ nomore than about 50, preferably no more than about 35, more preferably nomore than about 25 weight percent of the ethylene/α-olefin multi-blockinterpolymer or blend as an impact modifier.

Polymer Compositions which May be Impact Modified

Almost any thermoplastic polymer composition may be beneficially impactmodified by the addition of one or more of the ethylene/α-olefinmulti-block interpolymers discussed above. Such polymer compositionscomprise thermoplastic polyurethanes (e.g., Pellathane™ or Isoplast™made by The Dow Chemical Company), polyvinyl chlorides (PVCs),styrenics, polyolefins (including, e.g., ethylene carbon monoxidecopolymers (ECO) or linear alternating ECO copolymers such as thosedisclosed by U.S. Ser. No. 08/009,198, filed Jan. 22, 1993 (nowabandoned) in the names of John G. Hefner and Brian W. S. Kolthammer,entitled “Improved Catalysts For The Preparation of Linear CarbonMonoxide/Alpha Olefin Copolymers,” the disclosure of which isincorporated herein by reference, and ethylene/propylene carbon monoxidepolymers (EPCO)), various engineering thermoplastics (e.g.,polycarbonate, thermoplastic polyester, polyamides (e.g., nylon),polyacetals, or polysulfones), and mixtures thereof. Generally, thepolyolefin polymers which may be most frequently used are polyethylene(e.g., high density polyethylene, such as that produced by the slurry orgas phase polymerization processes) or polypropylene or propylene basedpolymers.

The properties of the high density polyethylene (HDPE) useful in thepresent invention vary depending upon the desired application.Typically, useful HDPE has a density of greater than 0.94 g/cm³.Preferably the density is greater than 0.95 g/cm³ but less than about0.97 g/cm³. The HDPE may be produced by any process including Cr andZiegler-Natta catalyst processes. The molecular weight of the HDPE foruse in the present invention varies depending upon the application butmay be conveniently indicated using a melt flow measurement according toASTM D-1238-03 Condition 190° C./2.16 kg and Condition 190° C./5.0 kg,which are known as 12 and 15, respectively. Melt flow determinations canalso be performed with even higher weights, such as in accordance withASTM D-1238, Condition 190° C./10.0 kg and Condition 190° C./21.6 kg,and are known as I₁₀ and 121, respectively. Melt flow rate is used forpropylene based polymers and is inversely proportional to the molecularweight of the polymer. Melt flow rate (MFR) is tested in accordance withASTM D 1238, Condition 230 C/2.16 kg (formerly Condition L). Thus, thehigher the molecular weight, the lower the melt flow rate, although therelationship is not linear. The lower limits for melt index (12) for theHDPE useful herein varies widely depending upon the application, e.g.,blow molding or injection molding, etc. but is generally at least about0.1 grams/10 minutes (g/10 min), preferably about 0.5 g/10 min,especially about 1 g/10 min to a high melt index limit of about 80 g/10min, preferably to about 25 g/10 min, and especially to about 20 g/10min. The molecular weight of the HDPE for use in the present invention,especially for pipe applications, varies depending upon the applicationcan also be indicated using a melt flow measurement according to ASTMD-1238, Condition 190 C/5 kg (and also known as I₅). The lower limitsfor melt index (I₅) for the HDPE useful herein is generally about 0.1grams/10 minutes (g/10 min), preferably about 0.2 g/10 min, to a highmelt index limit of about 0.6 g/10 min. Molecular weight distribution(Mw/Mn) of the selected HDPE can be narrow or broad, e.g., Mw/Mn fromabout 2 to as high as about 40.

The polypropylene is generally in the isotactic form of homopolymerpolypropylene, although other forms of polypropylene can also be used(e.g., syndiotactic or atactic). Polypropylene impact copolymers (e.g.,those wherein a secondary copolymerization step reacting ethylene withthe propylene is employed) and random copolymers (also reactor modifiedand usually containing 1.5-7% ethylene copolymerized with thepropylene), however, can also be used in the TPO formulations disclosedherein. A complete discussion of various polypropylene polymers iscontained in Modern Plastics Encyclopedia/89, mid October 1988 Issue,Volume 65, Number 11, pp. 86-92, the entire disclosure of which isincorporated herein by reference. The molecular weight and hence themelt flow rate of the polypropylene for use in the present inventionvaries depending upon the application. The melt flow rate for thepolypropylene useful herein is generally from about 0.1 grams/10 minutes(g/10 min) to about 100 g/10 min, preferably from about 0.5 g/10 min toabout 80 g/10 min, and especially from about 4 g/10 min to about 70 g/10min. The propylene polymer can be a polypropylene homopolymer, or it canbe a random copolymer or even an impact copolymer (which alreadycontains a rubber phase). Examples of such propylene polymers includeVISTAMAX (made by Exxon Mobil), VERSIFY and INSPIRE (made by The DowChemical Co.).

Methods for Making Blended Compositions

The blended compositions of the present invention are made by anyconvenient method, including dry blending the individual components andsubsequently melt mixing, either directly in the extruder used to makethe finished article (e.g., the automotive part), or by pre-melt mixingin a separate extruder (e.g., a Banbury mixer). Typically, the blendsare prepared by mixing or kneading the respective components at atemperature around or above the melt point temperature of one or both ofthe components. For most multiblock copolymers, this temperature may beabove 130° C., most generally above 145° C., and most preferably above150° C. Typical polymer mixing or kneading equipment that is capable ofreaching the desired temperatures and melt plastifying the mixture maybe employed. These include mills, kneaders, extruders (both single screwand twin-screw), Banbury mixers, calenders, and the like. The sequenceof mixing and method may depend on the final composition. A combinationof Banbury batch mixers and continuous mixers may also be employed, suchas a Banbury mixer followed by a mill mixer followed by an extruder.

Molding Operations

There are many types of molding operations which can be used to formuseful fabricated articles or parts from the TPO formulations disclosedherein, including various injection molding processes (e.g., thatdescribed in Modern Plastics Encyclopedia/89, Mid October 1988 Issue,Volume 65, Number 11, pp. 264-268, “Introduction to Injection Molding”and on pp. 270-271, “Injection Molding Thermoplastics”, the disclosuresof which are incorporated herein by reference) and blow moldingprocesses (e.g., that described in Modern Plastics Encyclopedia/89, MidOctober 1988 Issue, Volume 65, Number 11, pp. 217-218, “Extrusion-BlowMolding”, the disclosure of which is incorporated herein by reference)and profile extrusion. Some of the fabricated articles include fueltanks, outdoor furniture, pipes, automotive container applications,automotive bumpers, facia, wheel covers and grilles, as well as otherhousehold and personal articles, including, for example, freezercontainers. Of course, one skilled in the art can also combine polymersto advantageously use refractive index to improve, or maintain clarityof end use articles, such as freezer containers.

Additives

Additives such as antioxidants (e.g., hindered phenolics (e.g., Irganox™1010), phosphites (e.g., Irgafos™ 168)), cling additives (e.g., PIB),antiblock additives, pigments, fillers (e.g., talc, diatomaceous earth,nano-fillers, clay, metal particles, glass fibers or particles, carbonblack, other reinforcing fibers, etc.), and the like can also beincluded in the TPO formulations, to the extent that they do notinterfere with the enhanced formulation properties discovered byApplicants.

Improved Impact Strength

The compositions of the present invention have improved impact strength.Impact strength can be measured using, for example, Notched Izod impacttesting. Notched Izod Impact is a single point test that measures amaterials resistance to impact from a swinging pendulum. Izod impact isdefined as the kinetic energy needed to initiate fracture and continuethe fracture until the specimen is broken. Izod specimens are notched toprevent deformation of the specimen upon impact. The testing isconducted according to ASTM D56. Typically, compositions of thisinvention maintain or increase the notched Izod impact strength at 20°C. at least about 5%, preferably at least about 10%, more preferably atleast about 15% over a similar composition lacking ethylene/α-olefinmulti-block interpolymer. In addition, compositions of this inventionoften maintain or increase the notched Izod impact strength at −20° C.at least about 5%, preferably at least about 10%, more preferably atleast about 15% over a similar composition lacking ethylene/α-olefinmulti-block interpolymer. These novel impact compositions also haveimproved ductile-brittle transition temperature—that is, the transitionfrom ductile to brittle failure occurs at lower temperatures, typicallyat least about 5 C, preferably 10 C, and more preferably at least 15 Clower than the polymer that was impact modified, and lower than animpact modified composition using a random ethylene/alpha-olefincopolymer (at about the same density and melt index as the multi-block)as the impact modifier.

EXAMPLES AND COMPARATIVE EXAMPLES OF THE PRESENT INVENTION BlendPreparation

A series of high density polyethylene (Component 1)+impact modifyingpolymer (Component 2) blends are prepared by melting blending variousconcentrations of the two components. Prior to processing the blends apowdered antioxidant package is added to a physical mixture of the twocomponents in a sealed bag. The package consists of 200 ppm IRGNOX 1010and 400 ppm IRGAFOS 168. The physical polymer blend is tumbled todisperse the antioxidant throughout the resin sample. Each physicalblend is purged with nitrogen to help remove any residual oxygen fromthe bag.

The physical polymer blend+additive package combination is processed ona Haake system supplied with a Leistritz 18 mm twin screw extruder(L/D=30), a K-TRON K2VT20 twin screw auger feeder equipped with longpitch powder screws, two refrigerated water circulation bath quenchtanks, and a Berlyn PELL-2 4 blade strand chopper. A water circulator isattached to the jacket of the feed throat of the extruder and set at 20°C. to keep the polymer from melting and bridging the feed throat. Theextruder temperature zones are set at 150, 180, 200, 215, and 215° C.The extruder die is set at 215° C. Prior to extrusion a lid suppliedwith a nitrogen line is placed on top of the feed hopper. The transitionarea from the feeder discharge to the extruder feed throat cone issealed with heavy aluminum foil. The extruder is preheated, calibrated,and run empty with nitrogen flowing throughout the system to purge it ofoxygen.

The physical polymer/antioxidant blend is placed in the extruder feedhopper with the nitrogen supplied lid in place. The physical blend isfed to the extruder, melt blended and extruded. The extrudate is passedthrough the two quench tanks to solidify the melt into a polymer strand.The strand is passed through an air knife to remove water, andsubsequently chopped into pellets by the Berlyn strand chopper. Thepellets are collected from the discharge chute into a labeled bag.

Test Methods

Density

Resin density was measured by the Archimedes displacement method, ASTM D792-03, Method B, in isopropanol. Specimens were measured within 1 hourof molding after conditioning in the isopropanol bath at 23° C. for 8min to achieve thermal equilibrium prior to measurement. The specimenswere compression molded according to ASTM D-4703-00 Annex A with a 5 mininitial heating period at about 190° C. and a 15° C./min cooling rateper Procedure C. The specimen was cooled to 45° C. in the press withcontinued cooling until “cool to the touch”.

Melt Flow Rate by Extrusion Plastomer

Melt flow rate measurements were performed according to ASTM D-1238-03,Condition 190° C./2.16 kg and Condition 190° C./5.0 kg, which are knownas I₂ and I₅, respectively. Melt flow rate is inversely proportional tothe molecular weight of the polymer. Thus, the higher the molecularweight, the lower the melt flow rate, although the relationship is notlinear. Melt flow rate determinations can also be performed with evenhigher weights, such as in accordance with ASTM D-1238, Condition 190°C./10.0 kg and Condition 190° C./21.6 kg, and are known as 110 and I₂₁,respectively. Flow Rate Ratio (FRR) is the ratio of melt flow rate (I₂₁)to melt flow rate (I₂) unless otherwise specified. For example, in someinstances the FRR may be expressed as I₂₁/I₅, especially for highermolecular weight polymers.

Differential Scanning Calorimetry (DSC)

All of the results reported here were generated via a TA InstrumentsModel Q1000 DSC equipped with an RCS (refrigerated cooling system)cooling accessory and an auto sampler. A nitrogen purge gas flow of 50ml/min was used throughout. The sample was pressed into a thin filmusing a press at 175° C. and 1500 psi (10.3 MPa) maximum pressure forabout 15 seconds, then air-cooled to room temperature at atmosphericpressure. About 3 to 10 mg of material was then cut into a 6 mm diameterdisk using a paper hole punch, weighed to the nearest 0.001 mg, placedin a light aluminum pan (ca 50 mg) and then crimped shut. The thermalbehavior of the sample was investigated with the following temperatureprofile: The sample was rapidly heated to 180° C. and held isothermalfor 3 minutes in order to remove any previous thermal history. Thesample was then cooled to −40° C. at 10° C./min cooling rate and washeld at −40° C. for 3 minutes. The sample was then heated to 150° C. at10° C./min heating rate. The cooling and second heating curves wererecorded.

Gel Permeation Chromatography (GPC)

The following procedure was used to determine the molecular architectureof various polymer compositions. The chromatographic system consisted ofa Waters (Millford, Mass.) 150° C. high temperature gel permeationchromatograph equipped with a Precision Detectors (Amherst, Mass.)2-angle laser light scattering detector Model 2040. The 15° angle of thelight scattering detector was used for calculation purposes. Datacollection was performed using Viscotek TriSEC software version 3 and a4-channel Viscotek Data Manager DM400. The system was equipped with anon-line solvent degas device from Polymer Laboratories.

The carousel compartment was operated at 140° C. and the columncompartment was operated at 150° C. The columns used were four Shodex HT806M 300 mm, 13 μm columns and one Shodex HT803M 150 mm, 12 μm column.The solvent used was 1,2,4 trichlorobenzene. The samples were preparedat a concentration of 0.1 grams of polymer in 50 milliliters of solvent.The chromatographic solvent and the sample preparation solvent contained200 μg/g of butylated hydroxytoluene (BHT). Both solvent sources werenitrogen sparged. Polyethylene samples were stirred gently at 160° C.for 4 hours. The injection volume used was 200 microliters and the flowrate was 0.67 milliliters/min.

Calibration of the GPC column set was performed with 21 narrow molecularweight distribution polystyrene standards with molecular weights rangingfrom 580 to 8,400,000 g/mol which were arranged in 6 “cocktail” mixtureswith at least a decade of separation between individual molecularweights. The standards were purchased from Polymer Laboratories(Shropshire, UK). The polystyrene standards were prepared at 0.025 gramsin 50 milliliters of solvent for molecular weights equal to or greaterthan 1,000,000 g/mol, and 0.05 grams in 50 milliliters of solvent formolecular weights less than 1,000,000 g/mol. The polystyrene standardswere dissolved at 80° C. with gentle agitation for 30 minutes. Thenarrow standards mixtures were run first and in order of decreasinghighest molecular weight component to minimize degradation. Thepolystyrene standard peak molecular weights were converted topolyethylene molecular weights using equation 8 (as described inWilliams and Ward, J. Polym. Sci., Polym. Let., 6, 621 (1968)).:M _(polyethylene) =A×(M _(polystyrene))^(B)  (1)Where M is the molecular weight, A has a value of 0.41 and B is equal to1.0.

The Systematic Approach for the determination of multi-detector offsetswas done in a manner consistent with that published by Balke, Mourey, etal. (Mourey and Balke, Chromatography Polym. Chpt 12, (1992) and Balke,Thitiratsakul, Lew, Cheung, Mourey, Chromatography Polym. Chpt 13,(1992)), optimizing dual detector log results from Dow broad polystyrene1683 to the narrow standard column calibration results from the narrowstandards calibration curve using in-house software. The molecularweight data for off-set determination was obtained in a mannerconsistent with that published by Zimm (Zimm, B. H., J. Chem. Phys., 16,1099 (1948)) and Kratochvil (Kratochvil, P., Classical Light Scatteringfrom Polymer Solutions, Elsevier, Oxford, N.Y. (1987)). The overallinjected concentration used for the determination of the molecularweight was obtained from the sample refractive index area and therefractive index detector calibration from a linear polyethylenehomopolymer of 115,000 g/mol molecular weight which was measured inreference to NIST polyethylene homopolymer standard 1475. Thechromatographic concentrations were assumed low enough to eliminateaddressing 2nd Virial coefficient effects (concentration effects onmolecular weight).

Molecular weight calculations were performed using in-house software.The calculation of the number-average molecular weight, weight-averagemolecular weight, and z-average molecular weight were made according tothe following equations assuming that the refractometer signal isdirectly proportional to weight fraction. The baseline-subtractedrefractometer signal can be directly substituted for weight fraction inthe equations below. Note that the molecular weight can be from theconventional calibration curve or the absolute molecular weight from thelight scattering to refractometer ratio. An improved estimation ofz-average molecular weight, the baseline-subtracted light scatteringsignal can be substituted for the product of weight average molecularweight and weight fraction in equation (2) below:

$\begin{matrix}{\begin{matrix}\left. a \right) & {\overset{\_}{Mn} = \frac{\sum\limits^{i}{Wf}_{i}}{\sum\limits^{i}\left( {{Wf}_{i}/M_{i}} \right)}}\end{matrix}\begin{matrix}\left. b \right) & {\overset{\_}{Mw} = \frac{\sum\limits^{i}\left( {{Wf}_{i}*M_{i}} \right)}{\sum\limits^{i}{Wf}_{i}}}\end{matrix}\begin{matrix}\left. c \right) & {\overset{\_}{Mz} = \frac{\sum\limits^{i}\left( {{Wf}_{i}*M_{i}^{2}} \right)}{\sum\limits^{i}\left( {{Wf}_{i}*M_{i}} \right)}}\end{matrix}} & (2)\end{matrix}$

The term “bimodal” as used herein means that the MWD in a GPC curveexhibits two component polymers wherein one component polymer may evenexist as a hump, shoulder or tail relative to the MWD of the othercomponent polymer. A bimodal MWD can be deconvoluted into twocomponents: LMW component and HMW component. After deconvolution, thepeak width at half maxima (WAHM) and the average molecular weight (Mw)of each component can be obtained. Then the degree of separation (DOS)between the two components can be calculated by equation 3:

$\begin{matrix}{{DOS} = \frac{{\log\left( M_{w}^{H} \right)} - {\log\left( M_{w}^{L} \right)}}{{WAHM}^{H} + {WAHM}^{L}}} & (3)\end{matrix}$wherein M_(w) ^(H) and M_(w) ^(L) are the respective weight averagemolecular weight of the HMW component and the LMW component; andWAHM^(H) and WAHM^(L) are the respective peak width at the half maximaof the deconvoluted molecular weight distribution curve for the HMWcomponent and the LMW component. The DOS for the new composition isabout 0.01 or higher. In some embodiments, DOS is higher than about0.05, 0.1, 0.5, or 0.8. Preferably, DOS for the bimodal components is atleast about 1 or higher. For example, DOS is at least about 1.2, 1.5,1.7, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, or 5.0. In some embodiments, DOS isbetween about 5.0 to about 100, between about 100 to 500, or betweenabout 500 to 1,000. It should be noted that DOS can be any number in theabove range. In other embodiments, DOS exceeds 1,000.

ATREF

In some embodiments the bimodality of the distributions is characterizedby the weight fraction of the highest temperature peak in temperaturerising elution fractionation (typically abbreviated as “TREF”) data asdescribed, for example, in Wild et al., Journal of Polymer Science,Poly. Phys. Ed., Vol. 20, p. 441 (1982), in U.S. Pat. No. 4,798,081(Hazlitt et al.), or in U.S. Pat. No. 5,089,321 (Chum et al.), thedisclosures of all of which are incorporated herein by reference. Theweight fraction corresponding to the highest temperature peak isreferred to as the high-density fraction, since it contains little or noshort chain branching. The remaining fraction is therefore referred toas the short chain branching (SCB) fraction, since it represents thefraction which contains nearly all the short-chain branching inherent tothe polymer. This fraction is also the low density fraction.

In analytical temperature rising elution fractionation analysis (asdescribed in U.S. Pat. No. 4,798,081 and abbreviated herein as “ATREF”),the composition to be analyzed is dissolved in a suitable hot solvent(for example, 1,2,4 trichlorobenzene) and allowed to crystallized in acolumn containing an inert support (for example, stainless steel shot)by slowly reducing the temperature. The column is equipped with both aninfra-red detector and a differential viscometer (DV) detector. AnATREF-DV chromatogram curve is then generated by eluting thecrystallized polymer sample from the column by slowly increasing thetemperature of the eluting solvent (1,2,4 trichlorobenzene). TheATREF-DV method is described in further detail in WO 99/14271, thedisclosure of which is incorporated herein by reference. WO 99/14271also describes a suitable deconvolution technique for multicomponentpolymer blend compositions. The ATREF curve is also frequently calledthe short chain branching distribution (SCBD), since it indicates howevenly the comonomer (for example, hexene) is distributed throughout thesample in that as elution temperature decreases, comonomer contentincreases. The refractive index detector provides the short chaindistribution information and the differential viscometer detectorprovides an estimate of the viscosity average molecular weight. Adiscussion of the preceding may be found in L. G. Hazlitt, J. Appl.Polym. Sci.: Appl. Poly. Symp., 45, 25-37 (1990), which is incorporatedherein by reference.

Swell

The resin swell was measured by the Dow Lab Swell method which consistsof measuring as the time required by an extruded polymer strand totravel a pre-determined distance of 230 mm. The Göttfert Rheograph 2003with, 12 mm barrel and, equipped with a 10 LID capillary die was is usedfor the measurement. The measurement was carried out at 190° C., at twofixed shear rates, 300 s⁻¹ and t1,000 s⁻¹, respectively. The more theresin swells, the slower the free strand end travels and, the longer ittakes to cover 230 mm. The swell is reported as t300 and t1000 (s)values.

Rheology

The sample was compression molded into a disk for rheology measurement.The disks were prepared by pressing the samples into 0.071″ (1.8 mm)thick plaques and were subsequently cut into 1 in (25.4 mm) disks. Thecompression molding procedure was as follows: 365° F. (185° C.) for 5min at 100 psi (689 kPa); 365° F. (185° C.) for 3 min at 1500 psi (10.3MPa); cooling at 27° F. (15° C.)/min to ambient temperature (about 23°C.).

The resin rheology was measured on the ARES I (Advanced RheometricExpansion System) Rheometer. The ARES is a strain controlled rheometer.A rotary actuator (servomotor) applies shear deformation in the form ofstrain to a sample. In response, the sample generates torque, which ismeasured by the transducer. Strain and torque are used to calculatedynamic mechanical properties such as modulus and viscosity. Theviscoelastic properties of the sample were measured in the melt using aparallel plate set up, at constant strain (5%) and temperature (190°C.), and as a function of varying frequency (0.01 to 500 s⁻¹). Thestorage modulus (G′), loss modulus (G″), tan delta, and complexviscosity (eta*) of the resin were determined using RheometricsOrchestrator software (v. 6.5.8).

Low shear rheological characterization was performed on a RheometricsSR5000 in stress controlled mode, using a 25 mm parallel plates fixture.This type of geometry was preferred to cone and plate because itrequires only minimal squeezing flow during sample loading, thusreducing residual stresses.

Flexural and Secant Modulus Properties

The resin stiffness was characterized by measuring the Flexural Modulusat 5% strain and Secant Modulii at 1% and 2% strain, and a test speed of0.5 inch/min (13 mm/min) per ASTM D 790-99 Method B. The specimens werecompression molded according to ASTM D-4703-00 Annex 1 with a 5 mininitial heating period at about 190° C. and a 15° C./min cooling rateper Procedure C. The specimen was cooled to 45° C. in the press withcontinued cooling until “cool to the touch”.

Tensile Properties

Tensile strength at yield and elongation at break were measuredaccording to ASTM D-638-03. Both measurements were performed at 23° C.on rigid type IV specimens which were compression molded per ASTM D4703-00 Annex A-1 with a 5 min initial heating period at about 190° C.and a 15° C./min cooling rate per Procedure C. The specimen was cooledto 45° C. in the press with continued cooling until “cool to the touch”.

Environmental Stress Crack Resistance (ESCR)

The resin environmental stress crack resistance (ESCR) was measured perASTM-D 1693-01 Method B. Specimens were molded according to ASTM D4703-00 Annex A with a 5 min initial heating period at about 190° C. anda 15° C./min cooling rate per Procedure C. The specimen was cooled to45° C. in the press with continued cooling until “cool to the touch”.

In this test, the susceptibility of a resin to mechanical failure bycracking is measured under constant strain conditions, and in thepresence of a crack accelerating agent such as, soaps, wetting agents,etc. Measurements were carried out on notched specimens, in a 100% byvolume Igepal CO-630 (vendor Rhone-Poulec, N.J.) aqueous solution,maintained at 50° C. Ten specimens were evaluated per measurement. TheESCR value of the resin is reported as F₅₀, the calculated 50% failuretime from the probability graph.

Impact Strength

The Izod impact strength (ft·lb/in) was determined for notchedcompression molded plaques at 23° C. and −40° C. according to ASTM D256-03 Method A using a Tinius Olsen Izod Manual Impact device with a200 inch-pound capacity pendulum.

The Izod compression molded plaques were prepared per ASTM D 4703-00Annex A with a 5 min initial heating period at about 190° C. and a 15°C./min cooling rate per Procedure C. The specimen was cooled to about45° C. in the press with continued cooling until “cool to the touch”.

HDPE Impact Property Modification

The components used to produce impact modified high density polyethylene(HDPE) blends are listed in Table A.

TABLE A Blend Components Melt Flow Index Index Density I_(2.16) I_(21.6)Material Description Source (g/cm³) (dg/min) (dg/min) UNIVAL* Highdensity Commercial polymer 0.949 0.3 25 DMDA 6230 polyethylene from TheDow Chemical Company (TDCC) UNIVAL* High density Commercial polymer0.961 0.8 57 DMDH 6400 polyethylene from The Dow Chemical Company (TDCC)Example A Impact modifying TDCC 0.930 0.5 — multi block polymer ExampleB Impact modifying TDCC 0.909 0.5 — multi block polymer Example C Impactmodifying TDCC 0.922 0.5 — polymer Example D Impact modifying TDCC 0.9130.5 — polymer IRGANOX Polymer Ciba — — — 1010 stabilization additiveIRGAFOS Polymer Ciba — — — 168 stabilization additive

Polymerization Conditions

The polymerization process conditions used to produce the inventive andcomparative samples are described below.

Example A Multi Block Polymer Production Conditions

Continuous solution polymerizations are carried out in a computercontrolled autoclave reactor equipped with an internal stirrer. Purifiedmixed alkanes solvent (Isopar™ E available from ExxonMobil ChemicalCompany), ethylene at 2.70 lbs/hour (1.22 kg/hour), 1-octene, andhydrogen (where used) are supplied to a 3.8 L reactor equipped with ajacket for temperature control and an internal thermocouple. The solventfeed to the reactor is measured by a mass-flow controller. A variablespeed diaphragm pump controls the solvent flow rate and pressure to thereactor. At the discharge of the pump, a side stream is taken to provideflush flows for the catalyst and cocatalyst injection lines and thereactor agitator. These flows are measured by Micro-Motion mass flowmeters and controlled by control valves or by the manual adjustment ofneedle valves. The remaining solvent is combined with 1-octene,ethylene, and hydrogen (where used) and fed to the reactor. A mass flowcontroller is used to deliver hydrogen to the reactor as needed. Thetemperature of the solvent/monomer solution is controlled by use of aheat exchanger before entering the reactor. This stream enters thebottom of the reactor. The catalyst component solutions are meteredusing pumps and mass flow meters and are combined with the catalystflush solvent and introduced into the bottom of the reactor. The reactoris run liquid-full at 500 psig (3.45 MPa) with vigorous stirring.Product is removed through exit lines at the top of the reactor. Allexit lines from the reactor are steam traced and insulated.Polymerization is stopped by the addition of a small amount of waterinto the exit line along with any stabilizers or other additives andpassing the mixture through a static mixer. The product stream is thenheated by passing through a heat exchanger before devolatilization. Thepolymer product is recovered by extrusion using a devolatilizingextruder and water cooled pelletizer. Process details and results arecontained below in Table B.

Example B Multi Block Polymer Production Conditions

Continuous solution polymerizations are carried out in a computercontrolled well-mixed reactor equipped with an internal stirrer.Purified mixed alkanes solvent (Isopar™ E available from ExxonMobilChemical Company), ethylene at 5.96 lbs/hour (2.7 kg/hour), 1-octene,and hydrogen (where used) are supplied to a 5.0 L reactor equipped witha jacket for temperature control and an internal thermocouple. Thesolvent feed to the reactor is measured by a mass-flow controller. Avariable speed diaphragm pump controls the solvent flow rate andpressure to the reactor. At the discharge of the pump, a side stream istaken to provide flush flows for the catalyst and cocatalyst 1 injectionlines and the reactor agitator. These flows are measured by Micro-Motionmass flow meters and controlled by control valves or by the manualadjustment of needle valves. The remaining solvent is combined with1-octene, ethylene, and hydrogen (where used) and fed to the reactor. Amass flow controller is used to deliver hydrogen to the reactor asneeded. The temperature of the solvent/monomer solution is controlled byuse of a heat exchanger before entering the reactor. This stream entersthe bottom of the reactor. The catalyst component solutions are meteredusing pumps and mass flow meters and are combined with the catalystflush solvent and introduced into the bottom of the reactor. The reactoris run liquid-full at 406 psig (2.8 MPa) with vigorous stirring. Productis removed through exit lines at the top of the reactor. All exit linesfrom the reactor are steam traced and insulated. Polymerization isstopped by the addition of a small amount of water into the exit linealong with any stabilizers or other additives and passing the mixturethrough a static mixer. The product stream is then heated up throughheat exchangers, and passes two devolatizers in series before it iswater cooled Process details and results are contained below in Table B.

TABLE B Multi Block Polymer Sample Production Conditions Multi BlockMulti Block Polymer Polymer Process Conditions Units Example A Example BC₂H₄ kg/h (lb/h) 1.85 (4.08) 2.75 C₈H₁₆ kg/h (lb/h) 0.43 (0.95) 1.65Solv. kg/h (lb/h) 15.87 (34.99) 23 H₂ sccm 11.4 2 T ° C. 135.1 125 CatA1² Conc ppm 95.2 115.9 Cat A1 Flow kg/h (lb/h) 0.075 (0.165) 0.245 CatB2³ Conc ppm 41.8 59.2 Cat B2 Flow kg/h (lb/h) 0.145 (0.319) 0.21 DEZConc ppm 4055 5000 DEZ Flow kg/h (lb/h) 0.149 (0.328) 0.272 Cocat Concppm 1215.5 1665.6 Cocat Flow kg/h (lb/h) 0.112 (0.248) 0.16 Zn⁴ inPolymer ppm 347.1 802.6 Poly Rate⁵ kg/h (lb/h) 1.736 (3.827) 3 C₂H₄Conversion⁶ % 90 90 Solids % 9.564 11.538 Efficiency⁷ 132 73 ¹standardcm³/min²[N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(a-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafniumdimethyl³bis-(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)immino)zirconium dimethyl ⁴ppm in final product calculated by mass balance⁵polymer production rate ⁶weight percent ethylene conversion in reactor⁷efficiency, kg polymer/g M where g M = g Hf + g Z

Examples C and Example D are made in accordance with U.S. Pat. No.5,272,236 and U.S. Pat. No. 5,278,272, adjusted of course, for molecularweight and density.

Blend Preparation

A series of high density polyethylene a) DMDF 6230+impact modifyingpolymer (inventive or comparative polymer) blends and b) DMDH6400+impact modifying polymer (inventive or comparative polymer) blendsare prepared by melt blending various concentrations of the twocomponents (Table C). For comparison purposes the HDPE samples aresubjected to the same thermal extrusion history as the impact modifiedHDPE blend samples. The concentration of the comparative polymer in theblend is adjusted to produce the same overall blend density as theinventive-HDPE blends.

Prior to processing the blends a powdered antioxidant package is addedto a physical mixture of the two components in a sealed bag. The packageconsists of 200 ppm IRGNOX 1010 and 400 ppm IRGAFOS 168. The physicalpolymer blend is tumbled to disperse the antioxidant throughout theresin sample. Each physical blend is purged with nitrogen to help removeany residual oxygen from the bag.

TABLE C Blend Composition Impact modifying Impact DMDH 6400 polymerCalculated modifying concentration concentration Blend Sample polymer inblend in blend density Units — wt % wt % g/cm³ Unival DMDA 6230 (HD1)None 100 0 — Inventive Blend HD1A1_(I) Sample A 95 5 0.948  InventiveBlend HD1A2_(I) Sample A 90 10 0.9471 Inventive Blend HD1A3_(I) Sample A80 20 0.9451 Unival DMDH 6400H (HD2) None 100 0 — Inventive BlendHD2A1_(I) Sample A 95 5 0.9594 Inventive Blend HD2A2_(I) Sample A 90 100.9578 Comparative Blend HD2C1_(C) Sample C 90 10 0.9575 Inventive BlendHD2A3_(I) Sample A 80 20 0.9546 Comparative Blend HD2C2_(C) Sample C 8416 0.9546 Comparative Blend HD2C3_(C) Sample C 78 22 0.9526 InventiveBlend HD2B1_(I) Sample B 88 12 0.9544 Comparative Blend HD2D1_(C) SampleD 87 13 0.9545 Inventive Blend HD2B2_(I) Sample B 85 15 0.9528Comparative Blend HD2D2_(C) Sample D 83 17 0.9526

The physical polymer blend+additive package combination is processed ona Haake system supplied with a Leistritz 18 mm twin screw extruder(L/D=30), a K-TRON K2VT20 twin screw auger feeder equipped with longpitch powder screws, two refrigerated water circulation bath quenchtanks, and a Berlyn PELL-2 4 blade strand chopper. A water circulator isattached to the jacket of the feed throat of the extruder and set at 20°C. to keep the polymer from melting and bridging the feed throat. Theextruder temperature zones are set at 150, 180, 200, 215, and 215° C.The extruder die is set at 215° C. Prior to extrusion a lid suppliedwith a nitrogen line is placed on top of the feed hopper. The transitionarea from the feeder discharge to the extruder feed throat cone issealed with heavy aluminum foil. The extruder is preheated, calibrated,and run empty with nitrogen flowing throughout the system to purge it ofoxygen.

The physical polymer/antioxidant blend is placed in the extruder feedhopper with the nitrogen supplied lid in place. The physical blend isfed to the extruder, melt blended and extruded. The extrudate is passedthrough the two quench tanks to solidify the melt into a polymer strand.The strand is passed through an air knife to remove water, andsubsequently chopped into pellets by the Berlyn strand chopper. Thepellets are collected from the discharge chute into a labeled bag.

The blend density is calculated using the relation

$\frac{1}{\rho_{b}} = {\frac{w_{1}}{\rho_{1}} + \frac{1 - w_{1}}{\rho_{2}}}$Where, ρ_(b) is the blend density, w₁ the weight fraction of blendcomponent 1, ρ₁ the density of component 1, and ρ₂ the density of blendcomponent 2.

HDPE Blend Properties

The neat HDPE DMDH 6400 polymer and the blend samples are characterizedby various analytical methods.

The DSC overlay of HDPE DMDH 6400 and the DMDH 6400+inventive impactmodifying multi block polymer Example A, blends are shown in FIG. 8. Asingle DSC peak is observed indicating the compatibility of the twocomponents. The molecular weight distribution as characterized by GPC isshown in FIG. 9. The melt strength comparison is shown in FIG. 10.

The measured properties are listed in Table D.

TABLE D HDPE-Impact Modifying Polymer Blend Physical Properties Impactmodifying polymer Calculated Melt Flow Melt Impact conc in Blend IndexIndex Flow modifying blend density Density I_(2.16) I_(21.6) RatioSample polymer wt % g/cm³ g/cm³ dg/min dg/min I_(21.6)/I_(2.16) UnivalDMDA 6230 None 0 0.9501 0.26 28.0 108 (HD1) Inventive Blend HD1A1_(I)Sample A 5 0.948  0.9486 0.24 26.5 109 Inventive Blend HD1A2_(I) SampleA 10 0.9471 0.9474 0.26 25.2 96 Inventive Blend HD1A3_(I) Sample A 200.9451 0.9449 0.30 20.0 67 Unival DMDH 6400H None 0 — 0.9617 0.88 67.977 Inventive Blend HD2A1_(I) Sample A 5 0.9594 0.9597 0.83 97.1 117Inventive Blend HD2A2_(I) Sample A 10 0.9578 0.9582 0.77 50.8 66Comparative Blend Sample C 10 0.9575 0.9579 0.78 49.5 63 HD2C1_(C)Inventive Blend HD2A3_(I) Sample A 20 0.9546 0.9545 0.71 37.9 53Comparative Blend Sample C 16 0.9546 0.9536 0.71 40.8 57 HD2C2_(C)Comparative Blend Sample C 22 0.9526 0.9521 0.73 35.7 49 HD2C2_(C)Inventive Blend HD2B1_(I) Sample B 12 0.9544 0.9555 0.79 48.5 61Comparative Blend Sample D 13 0.9545 0.9546 0.74 43.8 59 HD2D1_(C)Inventive Blend HD2B2_(I) Sample B 15 0.9528 0.9536 0.73 45 62Comparative Blend Sample D 17 0.9526 0.9518 0.69 40 58 HD2D2_(C)

The DSC comparison of the inventive and comparative samples is shown inFIG. 11 and the ATREF comparison in FIG. 12.

The mechanical (stiffness-toughness) properties of the inventive andcomparative blends are listed in Table E.

TABLE E HDPE-Impact Modifying Polymer Blend Mechanical Properties ImpactTensile 23 deg C. −20 deg C. ESCR modifying Avg Yield Izod Izod 100%Impact polymer 2% Secant Avg Flex stress Tensile Impact Impact Igepal,modifying blend conc Density Modulus Modulus kpsi Elongation ft.lb/inft.lb/in 50 deg C., Sample polymer wt % g/cm³ kpsi (GPa) kpsi (GPa)(GPa) to break % (N · m/m) (N · m/m) F50 h Unival DMDA None 0 0.9501122.8 185.2 2.53 (135) 1.62 (87)  111 6230 (HD1) (0.846) (1.276)Inventive Blend Sample A 5 0.9486 123.9 182.7 3.18 (169) 1.97 (105) 207HD1A1_(I) (0.854) (1.260) Inventive Blend Sample A 10 0.9474 118.7 173.73.89 (208) 2.28 (121) 368 HD1A2_(I) (0.818) (1.120) Inventive BlendSample A 20 0.9449 112.4 162.4 7.37 (393) 2.86 (153) >800 HD1A3_(I)(0.775) (1.120) UNIVAL* None 0 0.9617 178.3 244.1 — — 2.23 (119) 2.19(117) 17 DMDH 6400H (1.229) (1.683) Inventive Blend Sample A 5 0.9597168.4 245.7 — — 3.36 (179) 2.49 (133) 24 HD2A1_(I) (1.161) (1.694)Inventive Blend Sample A 10 0.9582 163.2 245.1 — — 5.17 (276) 2.77 (148)31 HD2A2_(I) (1.125) (1.690) Comparative Sample C 10 0.9579 158.0 241.3— — 4.15 (222) 2.69 (144) 27 Blend HD2C1_(C) (1.089) (1.663) InventiveBlend Sample A 20 0.9545 150.4 233.5 4.01 1098  11.8 (631) 5.31 (284) 38HD2A3_(I) (1.037) (1.610) (0.028) Comparative Sample C 16 0.9536 154.6233.6 3.82 837 5.41 (289) 3.07 (164) 51 Blend HD2C2_(C) (1.066) (1.610)(0.026) Comparative Sample C 22 0.9521 139.1 206.3 — — 6.72 (359) 3.44(184) 107 Blend HD2C3_(C) (0.959) (1.422) Inventive Blend Sample B 120.9555 153.4 234.9 — — 10.87 (581)  2.96 (158) 26 HD2B1_(I) (1.057)(1.620) Comparative Sample D 13 0.9546 150.2 228.7 — — 10.46 (559)  3.89(208) 52 Blend HD2D1_(C) (1.035) (1.576) Inventive Blend Sample B 150.9536 146.4 221.4 3.63 883   13 (694) 4.18 (223) 29 HD2B2_(I) (1.010)(1.527) (0.025 Comparative Sample D 17 0.9518 145.8 216.8 3.62 831 12.1(646) 4.41 (236) 123 Blend HD2D2_(C) (1.005) (1.495) (0.025)

Increasing the concentration of the inventive multi block polymer,Example A, from 0 wt % to 10 wt % in the HD2 blend series, isaccompanied by a gradual improvement in the blend impact andenvironmental stress crack resistance properties (Table E). The blendstiffness, as characterized by the density and flex modulus, isbasically unchanged. However, on increasing the Example A polymerconcentration to 20% a significant improvement in the room temperatureand low temperature Izod impact performance of the blend (Inventiveblend HD2A3_(I)) is observed (Table E). The (DMDH 6400 HD2+Example A)blend performance was compared to that of (DNDH 6400 HD2+Example C)polymer blends. In order to minimize the variables a comparison is madebetween blends of similar overall density and melt index. The DMDH 6400HD2+Example A blends show a superior balance of stiffness and impactproperties compared to the DMDH 6400 HD2+Example C blends. The tensileproperties are also superior (Table E). The second inventive blendseries, (DMDH 6400 HD2+Example B) blends also have a good balance offlex modulus and impact resistance (Table E). In this case theperformance is similar to that of the comparative blends.

TPO Impact Property Modification

The raw materials used in preparing the compounded samples are shown inTable F. The materials were used in the as received condition except forthe ICP impact copolymer polypropylene sample. This sample was groundprior to use.

TABLE F Raw Materials Material Description Source ICP Impact copolymerpolypropylene Commercial polymer from The (35 MFR, 17% EPR) Dow ChemicalCompany Sample E Impact modifying multi block The Dow Chemical Companyethylene-octene copolymer Sample F Impact modifying multi block The DowChemical Company ethylene-butene copolymer AFFINITY ® EG * Impactmodifying ethylene-octene Commercial polymer from The 8150 (Sample G)copolymer (0.868 density/0.5 MI) Dow Chemical Company Jetfil 700C TalcCompacted talc (1.5 μm median Luzenac particle size) IRGANOX B225IRGANOX 1010 + IRGAFOS 168 Ciba (50:50 ratio) Calcium Stearate Moldrelease (NF grade) WitcoPolymerization Conditions

The multi block octene copolymer Sample E was produced using the processdescribed immediately below.

Continuous solution polymerizations are carried out in a computercontrolled autoclave reactor equipped with an internal stirrer. Purifiedmixed alkanes solvent (Isopar™ E available from ExxonMobil ChemicalCompany), ethylene at 2.70 lbs/hour (1.22 kg/hour), 1-octene, andhydrogen (where used) are supplied to a 3.8 L reactor equipped with ajacket for temperature control and an internal thermocouple. The solventfeed to the reactor is measured by a mass-flow controller. A variablespeed diaphragm pump controls the solvent flow rate and pressure to thereactor. At the discharge of the pump, a side stream is taken to provideflush flows for the catalyst and cocatalyst injection lines and thereactor agitator. These flows are measured by Micro-Motion mass flowmeters and controlled by control valves or by the manual adjustment ofneedle valves. The remaining solvent is combined with 1-octene,ethylene, and hydrogen (where used) and fed to the reactor. A mass flowcontroller is used to deliver hydrogen to the reactor as needed. Thetemperature of the solvent/monomer solution is controlled by use of aheat exchanger before entering the reactor. This stream enters thebottom of the reactor. The catalyst component solutions are meteredusing pumps and mass flow meters and are combined with the catalystflush solvent and introduced into the bottom of the reactor. The reactoris run liquid-full at 500 psig (3.45 MPa) with vigorous stirring.Product is removed through exit lines at the top of the reactor. Allexit lines from the reactor are steam traced and insulated.Polymerization is stopped by the addition of a small amount of waterinto the exit line along with any stabilizers or other additives andpassing the mixture through a static mixer. The product stream is thenheated by passing through a heat exchanger before devolatilization. Thepolymer product is recovered by extrusion using a devolatilizingextruder and water cooled pelletizer.

The multi block butene copolymer Sample F was produced using the processdescribed immediately below.

Continuous solution polymerizations are carried out in a computercontrolled well-mixed reactor equipped with an internal stirrer.Purified mixed alkanes solvent (Isopar™ E available from ExxonMobilChemical Company), ethylene at 5.96 lbs/hour (2.7 kg/hour), 1-butene,and hydrogen (where used) are supplied to a 5.0 L reactor equipped witha jacket for temperature control and an internal thermocouple. Thesolvent feed to the reactor is measured by a mass-flow controller. Avariable speed diaphragm pump controls the solvent flow rate andpressure to the reactor. At the discharge of the pump, a side stream istaken to provide flush flows for the catalyst and cocatalyst 1 injectionlines and the reactor agitator. These flows are measured by Micro-Motionmass flow meters and controlled by control valves or by the manualadjustment of needle valves. The remaining solvent is combined with1-octene, ethylene, and hydrogen (where used) and fed to the reactor. Amass flow controller is used to deliver hydrogen to the reactor asneeded. The temperature of the solvent/monomer solution is controlled byuse of a heat exchanger before entering the reactor. This stream entersthe bottom of the reactor. The catalyst component solutions are meteredusing pumps and mass flow meters and are combined with the catalystflush solvent and introduced into the bottom of the reactor. The reactoris run liquid-full at 406 psig (2.8 MPa) with vigorous stirring. Productis removed through exit lines at the top of the reactor. All exit linesfrom the reactor are steam traced and insulated. Polymerization isstopped by the addition of a small amount of water into the exit linealong with any stabilizers or other additives and passing the mixturethrough a static mixer. The product stream is then heated up throughheat exchangers, and passes two devolatizers in series before it iswater cooled

Compounding Conditions

All samples were compounded using a 30-mm W&P co-rotating twin-screwextruder with screw design ZSK30-0097. Vacuum was used during extrusion(18-20 inches of Hg). The tumble blended samples were fed in the feedthroat of the extruder. The compounding conditions are shown in Table G.It was desired to feed the sample at a rate to maintain around 80%torque. The extruder conditions were also adjusted to eliminate stranddrops.

TABLE G Compounding conditions Zone 1 Zone 2 Zone 3 Zone 4 Zone 5 MeltTemp. Temp. Temp. Temp. Temp. Temp. Screw Die Pressure (° C.) (° C.) (°C.) (° C.) (° C.) (° C.) rpm Torque % (psi) 167-190 184-206 197-213192-207 198-223 198-222 398-411 55-93 90-260

Samples were injection molded in a 90 ton Toyo Molding Machine.

Mold: 1 cavity non-vented ASTM ⅛″ T-bar and 1 cavity non-vented ASTM4″×⅛″ Disc

Molding Conditions:

Barrel temperature: 400° F.

Mold temperature: 140° F.

Fill time: 1.6 seconds

Packing pressure: 700 psi

Hold time: 25 seconds

Cool time: 25 seconds

Test Methods:

Izod—ASTM D256

Flex Properties—ASTM D790, 2 mm/min

Tensile Properties—ASTM D638, 50 mm/min

Sample Properties

The notched Izod impact strength-temperature dependence of inventiveblend samples ICP-E_(I) and ICP-F_(I), and comparative sample ICP-G_(C)is shown in Table H and plotted in FIG. 13.

TABLE H Notched Izod Impact Test Results Notched Izod impact testresults ASTM (ft-lb/in) ASTM ASTM −20° F. Component Talc Jetfil ASTM 14°F. ASTM −20° F. nIzod Sample # ICP Sample G Sample E Sample F 700 C. RTnIzod nIzod 0° F. nIzod nIzod retest ICP-G_(C) 63 27 — — 10 13.84 13.3510.1 1.753 1.539 comparative blend ICP-E_(I) 63 — 27 — 10 13.83 13.78 1210.288 9.447 inventive blend ICP-F_(t) 63 — — 27 10 12.25 11.91 9.56.735 7.561 Inventive blend

The inventive examples show higher low temperature toughness than thecomparative example.

Ductility of materials is often measured in terms of brittle-ductiletransition temperature defined as the temperature below which a materialfails in a brittle manner. For this comparison, the ductile-brittletransition temperature is defined as the temperature at which thenotched Izod impact strength reaches about 6 ft-lb/in. FIG. 13illustrates that the inventive examples (−20° F. for ICP-F_(I); −30° F.for ICP-E_(I)) show lower ductile-brittle transition temperature thanthe comparative example (−10° F. for ICP-G_(C)). Given that the modulusof all three examples is similar, it follows that lower amount of theinventive modifier may be added to the formulation to increase itsmodulus or stiffness. The resulting blend should still have similar lowtemperature toughness as the comparative example. These data indicatethat blends modified with the inventive polymer will have a betterstiffness-toughness balance than those modified with the comparativemodifiers.

Additional Blends Using OBC77 and REOC

The following polymers were employed in various blend compositions.

Inventive Example OBC77 is an ethylene/1-octene olefin block copolymer(OBC) having a composite 1-octene content of 77 wt. %, a compositedensity of 0.854 g/cc, a DSC peak melting point of 105° C., a hardsegment level based upon DSC measurement of 6.8 wt. %, an ATREFcrystallization temperature of 73° C., a hard segment density of 0.915g/cc, a soft segment density of 0.851 g/cc, a number average molecularweight of 188,254 daltons, a weight average molecular weight of 329,600daltons, a melt index at 190° C., 2.16 Kg of 1.0 dg/min and a melt indexat 190° C., 10 Kg of 37.0 dg/min.

Comparative Example REOC is a random ethylene/1-octene copolymer (REOC)having a density of 0.87 g/cc, a 1-octene content of 38 wt. %, a peakmelting point of 59.7° C., a number average molecular weight of 59,000daltons, a weight average molecular weight of 121,300 daltons, a meltindex of 1.0 dg/min at 190° C., 2.16 Kg and a melt index at 190° C., 10Kg of 7.5 dg/min. The product is commercially available from The DowChemical Company under the tradename ENGAGE® 8100.

The above polymers were melt mixed with a polypropylene homopolymer(PPH) having a melt flow index at 230° C., 2.16 Kg of 2.0 dg/min, and adensity of 0.9 g/cc. The product is commercially available under thecommercial name of Dow Polypropylene H110-02N. For all blends, 0.2 partsper 100 total polymer of a 1:1 blend of phenolic/phosphite antioxidant,available under the tradename Irganox B215, was added for heatstability. This additive is designated as AO in Table I

The following mixing procedure was used. A 69 cc capacity Haake batchmixing bowl fitted with roller blades was heated to 200° C. for allzones. The mixing bowl rotor speed was set at 30 rpm and was chargedwith PPH, allowed to flux for one minute, then charged with AO andfluxed for an additional two minutes. The mixing bowl was then chargedwith either Inventive Example OBC77, Comparative Example REOC, or a 1:1blend of Inventive Example OBC77 and Comparative Example REOC. Afteradding the elastomer, the mixing bowl rotor speed was increased to 60rpm and allowed to mix for an additional 3 minutes. The mixture was thenremoved from the mixing bowl and pressed between Mylar sheets sandwichedbetween metal platens and compressed in a Carver compression moldingmachine set to cool at 15° C. with a pressure of 20 kpsi. The cooledmixture was then compression molded into 2 inch×2 inch×0.06 inch plaquesvia compression molding for 3 minutes at 190° C., 2 kpsi pressure for 3minutes, 190° C., 20 kpsi pressure for 3 minutes, then cooling at 15°C., 20 kpsi for 3 minutes. The mixtures prepared under the proceduredescribed above are listed in the table below.

Blends with PP Mixture1 Mixture 2 Mixture 3 Ingredient parts parts partsPPH 70 70 70 Inventive Example OBC77 30 0 15 Comparative Example REOC 030 15 AO 0.2 0.2 0.2

Compression molded plaques were trimmed so that sections could becollected at the core. The trimmed plaques were cryopolished prior tostaining by removing sections from the blocks at −60° C. to preventsmearing of the elastomer phases. The cryo-polished blocks were stainedwith the vapor phase of a 2% aqueous ruthenium tetraoxide solution for 3hrs at ambient temperature. The staining solution was prepared byweighing 0.2 gm of ruthenium (III) chloride hydrate (RuCl3×H2O) into aglass bottle with a screw lid and adding 10 ml of 5.25% aqueous sodiumhypochlorite to the jar. The samples were placed in the glass jar usinga glass slide having double sided tape. The slide was placed in thebottle in order to suspend the blocks about 1 inch above the stainingsolution. Sections of approximately 100 nanometers in thickness werecollected at ambient temperature using a diamond knife on a Leica EM UC6microtome and placed on 400 mesh virgin TEM grids for observation.

Bright-field images were collected on a JEOL JEM 1230 operated at 100 kVaccelerating voltage and collected using Gatan 791 and Gatan 794 digitalcameras. The images were post processed using Adobe Photoshop 7.0.

FIGS. 14, 15, and 16 are transmission electron micrographs of Mixtures1, 2 and Mixture 3 above, respectively. The dark domains are the RuCl₃XH₂O stained ethylene/1-octene polymers. As can be seen, the domainscontaining Inventive Example OBC77 are much smaller than ComparativeExample REOC. The domain sizes for Inventive Example OBC77 range from<0.1 to 2 μm, whereas the domain sizes for Comparative Example REOC fromabout 0.2 to over 5 μm. Mixture 3 contains a 1:1 blend of InventiveExample OBC77 and Comparative Example REOC. Note that the domain sizesfor Mixture 3 are well below those for Mixture 2, indicating thatInventive Example OBC77 is improving the compatibility of ComparativeExample REOC with PPH.

Image analysis of Mixtures 1, 2, and 3. was performed using Leica QwinPro V2.4 software on 5 k×TEM images. The magnification selected forimage analysis depended on the number and size of particles to beanalyzed. In order to allow for binary image generation, manual tracingof the elastomer particles from the TEM prints was carried out using ablack Sharpie marker. The traced TEM images were scanned using a HewlettPackard Scan Jet 4c to generate digital images. The digital images wereimported into the Leica Qwin Pro V2.4 program and converted to binaryimages by setting a gray-level threshold to include the features ofinterest. Once the binary images were generated, other processing toolswere used to edit images prior to image analysis. Some of these featuresincluded removing edge features, accepting or excluding features, andmanually cutting features that required separation. Once the particlesin the images were measured, the sizing data was exported into aspreadsheet that was used to create bin ranges for the rubber particles.The sizing data was placed into appropriate bin ranges and a histogramof particle lengths (maximum particle length) versus percent frequencywas generated. Parameters reported were minimum, maximum, averageparticle size and standard deviation. The table below shows the resultsof the image analysis of mixtures domain sizes.

Mixture Number 1 2 3 Count (number) 718 254 576 Max. Domain Size (mm)5.1 15.3 2.9 Minimum Domain Size (mm) 0.3 0.3 0.3 Mean Domain Size (mm)0.8 1.9 0.8 Standard Deviation (mm) 0.5 2.2 0.4

The results clearly showed that that both Mixtures 1 and 2 exhibitedsignificantly lower mean elastomer domain size and narrower domain sizedistribution. The beneficial interfacial effect from Inventive Example 1can be clearly seen as a 1:1 blend with Comparative Example A in Mixture3. The resultant domain mean particle size and range are nearlyidentical to Mixture 1, which contains only Inventive Example 1 as theelastomer component.

Procedure for Making Inventive Example OBC77

The procedure for making OBC77 used in the aforementioned mixtures is asfollows: A single one gallon autoclave continuously stirred tank reactor(CSTR) was employed for the experiments. The reactor runs liquid full atca. 540 psig with process flow in the bottom and out the top. Thereactor is oil jacketed to help remove some of the heat of reaction.Primary temperature control is achieved by two heat exchangers on thesolvent/ethylene addition line. ISOPAR® E, hydrogen, ethylene, and1-octene were supplied to the reactor at controlled feed rates.

Catalyst components were diluted in an air-free glove box. The twocatalysts were fed individually at the desired ratio from differentholding tanks. To avoid catalyst feed line plugging, the catalyst andcocatalyst lines were split and fed separately into the reactor. Thecocatalyst was mixed with the diethylzinc chain shuttling agent beforeentry into the reactor.

Prime product was collected under stable reactor conditions afterseveral hourly product samples showed no substantial change in meltindex or density. The products were stabilized with a mixture ofIRGANOX® 1010, IRGANOX® 1076 and IRGAFOS®176.

Temperature C2 flow C8 flow H2 flow Density I2 I10/I2 (° C.) (kg/hr)(kg/hr) (sccm) 0.8540 1.05 37.90 120.0 0.600 5.374 0.9 Catalyst Al C2Polymer Efficiency (kg Catalyst Al Catalyst conversion C8 conversionproduction polymer/g total Flow Concentration (%) (%) % solids rate(kg/hr) metal) (kg/hr) (ppm) 89.9 20.263 10.0 1.63 287 0.043 88.099 A2Catalyst A2 Catalyst RIBS-2 DEZ Flow Concentration RIBS-2 FlowConcentration DEZ flow concentration (kg/hr) (ppm) Mole % A2 (kg/hr)(ppm) (kg/hr) (ppm Zn) 0.196 9.819 50.039 0.063 1417 0.159 348

Structures for Catalysts A1 and A2 are shown below:

Examples of Maleic Anhydride Modified Polymers

Ethylene-octene multi-block interpolymer base polymers were firstprepared as described in PCT Application No. PCT/US2005/008917, filed onMar. 17, 2005, which in turn claims priority to U.S. ProvisionalApplication No. 60/553,906, filed Mar. 17, 2004 each of which isincorporated by reference herein. Comparative base polymers are randomethylene-octene copolymers prepared using a constrained geometrycatalyst such as those sold under the name AFFINITY® by The Dow ChemicalCompany.

Density Melt Index (I₂) Copolymer Base Polymer (g/cc) g/10 min TypeBlock Type AFFINITY ® 0.875 3.0 g/10 random NA KC8852 AFFINITY ® 0.875.0 g/10 random NA EG8200 Multi-block 0.877 4.7 block long R21Multi-block 0.877 4.6 block short R22 NA = Not Applicable Melt Index(I₂): 190° C./2.16 kgMulti-block R21 and Multi-block R22 Continuous Solution Polymerization,Catalyst A1/B2+DEZ

Continuous solution polymerizations were carried out in a computercontrolled, well-mixed reactor. Purified mixed alkanes solvent (Isopar™E available from Exxon Mobil, Inc.), ethylene, 1-octene, and hydrogen(where used) were combined and fed to a 102 L reactor. The feeds to thereactor were measured by mass-flow controllers. The temperature of thefeed stream was controlled by use of a glycol cooled heat exchangerbefore entering the reactor. The catalyst component solutions weremetered using pumps and mass flow meters. The reactor was runliquid-full at approximately 550 psig pressure. Upon exiting thereactor, water and additive were injected in the polymer solution. Thewater hydrolyzes the catalysts, and terminates the polymerizationreactions. The post reactor solution was then heated in preparation fora two-stage devolatization. The solvent and unreacted monomers wereremoved during the devolatization process. The polymer melt was pumpedto a die for underwater pellet cutting. Process conditions aresummarized in the following table.

Process Conditions for Multi-block R21 and Multi-block R22

Multi-block R21 Multi-block R22 C₂H₄ (lb/hr)* 55.53 54.83 C₈H₁₆ (lb/hr)30.97 30.58 Solvent (lb/hr) 324.37 326.33 H₂ (sccm¹) 550 60 T (° C.) 120120 Cat. A1² (ppm) 600 600 Cat. A1 Flow (lb/hr) 0.216 0.217 Cat. B2³(ppm) 200 200 Cat. B2 Flow (lb/hr) 0.609 0.632 DEZ Conc. wt % 3.0 3.0DEZ Flow (lb/hr) 0.69 1.39 Cocat. 1 Conc. (ppm) 4500 4500 Cocat. 1 Flow(lb/hr) 0.61 0.66 Cocat. 2 Conc. (ppm) 525 525 Cocat. 2 Flow (lb/hr)0.33 0.66 [DEZ]⁴ in polymer (ppm) 246 491 Polymerization Rate⁵ 84.1382.56 (lb/hr) Conversion⁶ (wt %) 88.9 88.1 Polymer (wt %) 17.16 17.07Efficiency⁷ 293 280 *1 lb/hr = 0.45 kg/hr ¹standard cm³/min²[N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafniumdimethyl³bis-(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)immino)zirconium dibenzyl ⁴ppm in final product calculated by mass balance⁵polymer production rate ⁶weight percent ethylene conversion in reactor⁷efficiency, kg polymer/g M, where, g M = g Hf + g ZMelt Maleation—Grafting MAH to Olefin Interpolymer in a Twin-ScrewExtruder

MAH-grafted resins were prepared in a continuous reactive extrusionprocess using a twin-screw extruder. The resins used for this processwere AFFINITY®KC8852, AFFINITY® EG8200, Multi-block R21, and Multi-blockR22 as described above. The apparatus was a 30-mm ZSK-30 extruder with alength-to-diameter ratio of 35.67. The temperature set point in theextruder was 235° C. The screw rotation rate was 300 RPM. Resin pelletswere fed to the extruder at a rate of 10 lb/hr. The peroxide initiatorwas 2,5-bis(t-butylperoxy)-2,5-dimethylhexane. A solution, containingapproximately 1.24 wt % peroxide, 49.38 wt % MAH, and 49.38 wt % methylethyl ketone, was fed into the extruder at a rate of approximately 6.17g/min. This addition rate corresponded to the addition of 4 wt % MAH and1000 ppm peroxide based on the mass of resin. A vacuum port wasinstalled at the end of the extruder to remove methyl ethyl ketone andexcess, ungrafted MAH. The grafted resin exited the extruder and waspelletized and collected.

Approximately 2.5 g of each grafted resin was dissolved in 100 mL ofboiling xylene, and then precipitated by pouring the solution into fivevolumes of acetone. The solids were collected, dried, and titrated todetermine the level of grafted MAH. The EO870 resin contained 1.85 wt %grafted MAH. The EO875 resin contained 1.85 wt % grafted MAH. TheMulti-block R21 resin contained 1.80 wt % grafted MAH. The Multi-blockR22 resin contained 1.49 wt % MAH. The grafted resins were blended witha polyamide resin as discussed below.

MAH-grafted Resin/Polyamide Blends

MAH-Grafted Resins

Melt index data on MAH-grafted resins are shown below.

GPC and Melt Index Data Wt % grafted I₂ Resin MAH g/10 min 1.MAH-g-AFFINITY ® EG8200* 1.85 0.0912 2. MAH-g-AFFINITY ® KC8852* 1.850.049 3. MAH-g-Multi-block R22 1.49 0.2393 4. MAH-g-Multi-block R21 1.800.1482 *Comparative resins I₂: 190 C/2.16 kgBlends: Representative Procedure

Approximately 454 grams of the maleic anhydride grafted resin(MAH-g-EO870, MAH-g-875, MAH-g-Multi-block R22 or the MAH-g-Multi-blockR21) was pellet blended with 1816 grams of a polyamide (Ultramide® B-3,available from BASF), by feeding both resins into a 25 mm Haake twinscrew extruder at an instantaneous rate of 2724 grams per hour. Theextruder temperature profile was a constant 250° C. The collected samplewas subsequently injection molded to produce ASTM test bars for IZOD andflexural modulus testing. Mechanical Test data is summarized in thetable below.

Mechanical Data

Avg. Avg. Avg. Secant Avg. Izod- Flex. Flex. Mod. @ RT @ B- Avg. Colorof Strength Mod. 1% 3833 Izod molded Resin psi ksi ksi ft-lbs/in J/mplaques 1. MAH-g-, 5873 267 266 7.391 394.6 tan AFFINITY ® EG8200 2.MAH-g- 5799 265 265 10.08 537.9 tan AFFINITY ® KC8852 3. MAH-g-Multi-5864 264 264 8.624 460.4 tan blockR22 4. MAH-g-Multi- 5463 246 246 7.346392.2 tan blockR21

The lower viscosity Multi-block resins have comparable or even bettermechanical properties, compared to the higher viscosity comparativeresins.

The resins were made into injection molded plaques and tested for impactproperties. The results are shown in the table below.

Impact Avg Flexural Tester Impact Tester Average Izod Resin Modulus(ksi) (30° C.) (Room Temp) Impact (J/m) 1. MAH-g-, 267 with standard48.62 56.99 394.6    AFFINITY ® EG8200 deviation of 6 2. MAH-g- 265 withstandard 58.18 56.64 537.9    AFFINITY ® KC8852 deviation of 4 3.MAH-g-Multi- 264 with standard 68.17 63.25 460.4    blockR22 deviationof 10 4. MAH-g-Multi- 246 with standard 63.92 66.25 392.2    blockR21deviation of 9

Note: the Inventive polymers (Run # 3 & 4) have significantly higherimpact resistance at low temperature vs. the comparative samples (Run #1 & 2). Sample # 3 has the best balance between high modulus and highimpact. This improved impact is demonstrated at both room temperatureand at low temperature. The test pieces were injection molded plaquesand the test was completed using the procedure as outlined in ASTM D3763 (Injection Molded Parts). Flex modulus was done according to ASTMD-790 and Izod impact was done according to D-256.

While the invention has been described with respect to a limited numberof embodiments, the specific features of one embodiment should not beattributed to other embodiments of the invention. No single embodimentis representative of all aspects of the invention. In some embodiments,the compositions or methods may include numerous compounds or steps notmentioned herein. In other embodiments, the compositions or methods donot include, or are substantially free of, any compounds or steps notenumerated herein. Variations and modifications from the describedembodiments exist. Finally, any number disclosed herein should beconstrued to mean approximate, regardless of whether the word “about” or“approximately” is used in describing the number. The appended claimsintend to cover all those modifications and variations as falling withinthe scope of the invention.

We claim:
 1. A composition comprising: A) a thermoplastic polymercomposition, and B) an impact modifying amount of an ethylene/α-olefinmulti-block interpolymer polymerized in the presence of a catalystcomposition comprising a first olefin polymerization catalyst having afirst comonomer incorporation index, a second olefin polymerizationcatalyst having a second comonomer incorporation index different thanthe first comonomer incorporation index, and a chain shuttling agent,wherein the ethylene/α-olefin interpolymer comprises at least 50 molepercent ethylene and: (a) has a Mw/Mn from about 1.7 to about 3.5, atleast one melting point, Tm, in degrees Celsius, and a density, d, ingrams/cubic centimeter, wherein the numerical values of Tm and dcorrespond to the relationship:Tm>−2002.9+4538.5(d)−2422.2(d)²; and either: (b) has a Mw/Mn from about1.7 to about 3.5, and is characterized by a heat of fusion, ΔH in J/g,and a delta quantity, ΔT, in degrees Celsius defined as the temperaturedifference between the tallest DSC peak and the tallest CRYSTAF peak,wherein the numerical values of ΔT and ΔH have the followingrelationships:ΔT>−0.1299(ΔH)+62.81 for ΔH greater than zero and up to 130 J/g,Δ≧48° C. for ΔH greater than 130 J/g, wherein the CRYSTAF peak isdetermined using at least 5 percent of the cumulative polymer, and ifless than 5 percent of the polymer has an identifiable CRYSTAF peak,then the CRYSTAF temperature is 30° C.; or (c) is characterized by anelastic recovery, Re, in percent at 300 percent strain and 1 cyclemeasured with a compression-molded film of the ethylene/α-olefininterpolymer, and has a density, d, in grams/cubic centimeter, whereinthe numerical values of Re and d satisfy the following relationship whenthe ethylene/α-olefin interpolymer is substantially free of across-linked phase:Re>1481−1629(d); or (d) has a molecular fraction which elutes between40° C. and 130° C. when fractionated using TREF, characterized in thatthe fraction has a molar comonomer content of at least 5 percent higherthan that of a comparable random ethylene interpolymer fraction elutingbetween the same temperatures, wherein said comparable random ethyleneinterpolymer has the same comonomer(s) and has a melt index, density,and molar comonomer content (based on the whole polymer) within 10percent of that of the ethylene/α-olefin interpolymer.
 2. Thecomposition of claim 1 wherein the thermoplastic polymer compositioncomprises one or more polymers selected from the group consisting ofpolyurethanes, polyvinyl chlorides, styrenics, polyolefins,polycarbonates, thermoplastic polyester, polyamides, polyactals, andpolysulfones.
 3. The composition of claim 1 wherein the thermoplasticpolymer composition comprises polypropylene.
 4. The composition of claim1 wherein the thermoplastic polymer composition comprises high densitypolyethylene.
 5. The composition of claim 1 wherein theethylene/α-olefin interpolymer has a Mw/Mn from about 1.7 to about 3.5,and is characterized by a heat of fusion, ΔH in J/g, and a deltaquantity, ΔT, in degrees Celsius defined as the temperature differencebetween the tallest DSC peak and the tallest CRYSTAF peak, wherein thenumerical values of ΔT and ΔH have the following relationships:ΔT>−0.1299(ΔH)+62.81 for ΔH greater than zero and up to 130 J/g,ΔT≧48° C. for ΔH greater than 130 J/g, wherein the CRYSTAF peak isdetermined using at least 5 percent of the cumulative polymer, and ifless than 5 percent of the polymer has an identifiable CRYSTAF peak,then the CRYSTAF temperature is 30° C.
 6. The composition of claim 1wherein the ethylene/α-olefin interpolymer is characterized by anelastic recovery, Re, in percent at 300 percent strain and 1 cyclemeasured with a composition-molded film of the ethylene/α-olefininterpolymer, and has a density, d, in grams/cubic centimeter, whereinthe numerical values of Re and d satisfy the following relationship whenethylene/α-olefin interpolymer is substantially free of a cross-linkerphase:Re>1481−1629(d).
 7. The composition of claim 1 wherein theethylene/α-olefin interpolymer has a molecular fraction which elutesbetween 40° C. and 130° C. when fractionated using TREF, characterizedin that the fraction has a molar comonomer content of at least 5 percenthigher than that of a comparable random ethylene interpolymer fractioneluting between the same temperatures, wherein said comparable randomethylene interpolymer has the same comonomer(s) and has a melt index,density, and molar comonomer content (based on the whole polymer) within10 percent of that of the ethylene/α-olefin interpolymer.
 8. Afabricated article made from the composition of claim
 1. 9. Acomposition of claim 1, further comprising at least one additiveselected from the group consisting of antioxidants, phosphites, clingadditives, antiblock additives, pigments, and fillers.
 10. A compositioncomprising: A) at least one propylene polymer; and B) from about 1 toabout 25 weight percent based on the total composition of anethylene/α-olefin multi-block interpolymer polymerized in the presenceof a catalyst composition comprising a first olefin polymerizationcatalyst having a first comonomer incorporation index, a second olefinpolymerization catalyst having a second comonomer incorporation indexdifferent than the first comonomer incorporation index, and a chainshuttling agent, wherein the ethylene/α-olefin interpolymer comprises atleast 50 mole percent ethylene and: (a) has a Mw/Mn from about 1.7 toabout 3.5, at least one melting point, Tm, in degrees Celsius, and adensity, d, in grams/cubic centimeter, wherein the numerical values ofTm and d correspond to the relationship:Tm>−2002.9+4538.5(d)−2422.2(d)²; and either: (b) has a Mw/Mn from about1.7 to about 3.5, and is characterized by a heat of fusion, ΔH in J/g,and a delta quantity, ΔT, in degrees Celsius defined as the temperaturedifference between the tallest DSC peak and the tallest CRYSTAF peak,wherein the numerical values of ΔT and ΔH have the followingrelationships:ΔT>−0.1299(ΔH)+62.81 for ΔH greater than zero and up to 130 J/g,ΔT≧48° C. for ΔH greater than 130 J/g, wherein the CRYSTAF peak isdetermined using at least 5 percent of the cumulative polymer, and ifless than 5 percent of the polymer has an identifiable CRYSTAF peak,then the CRYSTAF temperature is 30° C.; or (c) is characterized by anelastic recovery, Re, in percent at 300 percent strain and 1 cyclemeasured with a compression-molded film of the ethylene/α-olefininterpolymer, and has a density, d, in grams/cubic centimeter, whereinthe numerical values of Re and d satisfy the following relationship whenthe ethylene/α-olefin interpolymer is substantially free of a crosslinked phase:Re>1481−1629(d); or (d) has a molecular fraction which elutes between40° C. and 130° C. when fractionated using TREF, characterized in thatthe fraction has a molar comonomer content of at least 5 percent higherthan that of a comparable random ethylene interpolymer fraction elutingbetween the same temperatures, wherein said comparable random ethyleneinterpolymer has the same comonomer(s) and has a melt index, density,and molar comonomer Content (based on the whole polymer) within 10percent of that of the ethylene/α-olefin interpolymer.
 11. Thecomposition of claim 10 wherein the notched Izod impact strength at 20°C. is at least 10% higher as compared to the same propylene polymercomposition without the ethylene/α-olefin interpolymer.
 12. Thecomposition of claim 10 wherein the notched Izod impact strength at 20°C. is at least 10% higher as compared to the same propylene polymercomposition without the ethylene/α-olefin interpolymer.
 13. Thecomposition of claim 10 wherein the notched Izod impact strength at 20°C. is at least 15% higher as compared to the same propylene polymercomposition without the ethylene/α-olefin interpolymer.
 14. Thecomposition of claim 10 wherein the ethylene/α-olefin interpolymer wasprepared by using from about 50 ppm to about 300 ppm chain shuttlingagent.
 15. The composition of claim 14 wherein the chain shuttling agentis diethyl zinc.
 16. The composition of claim 10 wherein theethylene/α-olefin interpolymer has a density of from about 0.85 to about0.93 g/cm³.
 17. A fabricated article made from the composition of claim10.
 18. A composition comprising: A) high density polyethylene having adensity of at least about 0.94 g/cm³; and B) from about 1 to about 25weight percent based on the total composition of an ethylene/α-olefinmulti-block interpolymer polymerized in the presence of a catalystcomposition comprising a first olefin polymerization catalyst having afirst comonomer incorporation index, a second olefin polymerizationcatalyst having a second comonomer incorporation index different thanthe first comonomer incorporation index, and a chain shuttling agent,wherein the ethylene/α-olefin interpolymer comprises at least 50 molepercent ethylene and: (a) has a Mw/Mn from about 1.7 to about 3.5, atleast one melting point, Tm, in degrees Celsius, and a density, d, ingrams/cubic centimeter, wherein the numerical values of Tm and dcorrespond to the relationship:Tm>−2002.9+4538.5(d)−2422.2(d)²; and either: (b) has a Mw/Mn from about1.7 to about 3.5, and is characterized by a heat of fusion, ΔH in J/g,and a delta quantity, ΔT, in degrees Celsius defined as the temperaturedifference between the tallest DSC peak and the tallest CRYSTAF peak,wherein the numerical values of ΔT and ΔH have the followingrelationships:ΔT>−0.299(ΔH)+62.81 for ΔH greater than zero and up to 130 J/g,ΔT≧48° C. for ΔH greater than 130 J/g, wherein the CRYSTAF peak isdetermined using at least 5 percent of the cumulative polymer, and ifless than 5 percent of the polymer has an identifiable CRYSTAF peak,then the CRYSTAF temperature is 30° C.; or (c) is characterized by anelastic recovery, Re, in percent at 300 percent strain and 1 cyclemeasured with a compression-molded film of the ethylene/α-olefininterpolymer, and has a density, d, in grams/cubic centimeter, whereinthe numerical values of Re and d satisfy the following relationship whenthe ethylene/α-olefin interpolymer is substantially free of across-linked phase:Re>1481−1629(d); or (d) has a molecular fraction which elutes between40° C. and 130° C. when fractionated using TREF, characterized in thatthe fraction has a molar comonomer content of at least 5 percent higherthan that of a comparable random ethylene interpolymer fraction elutingbetween the same temperatures, wherein said comparable random ethyleneinterpolymer has the same comonomer(s) and has a melt index, density,molar comonomer content (based on the whole polymer) within 10 percentof that of the ethylene/α-olefin interpolymer.
 19. The composition ofclaim 18 wherein the notched Izod impact strength at 20° C. is at least5% higher as compared to the same high density polyethylene compositionwithout the ethylene/α-olefin interpolymer.
 20. The composition of claim18 wherein the notched Izod impact strength at 20° C. is at least 10%higher as compared to the same high density polyethylene compositionwithout the ethylene/α-olefin interpolymer.
 21. The composition of claim18 wherein the notched Izod impact strength at 20° C. is at least 15%higher as compared to the same high density polyethylene compositionwithout the ethylene/α-olefin interpolymer.
 22. The composition of claim18 wherein the ethylene/α-olefin interpolymer was prepared by using fromabout 50 ppm to about 300 ppm chain shuttling agent.
 23. The compositionof claim 22 wherein the chain shuttling agent is diethyl zinc.
 24. Thecomposition of claim 18 wherein the ethylene/α-olefin interpolymer has adensity of form about 0.85 to about 0.93 g/cm³.
 25. A fabricated articlemade from the composition of claim
 18. 26. A composition comprising: A)a thermoplastic polymer composition; and B) an impact modifying amountof an ethylene/α-olefin multi-block interpolymer polymerized in thepresence of a catalyst composition comprising a first olefinpolymerization catalyst having a first comonomer incorporation index asecond olefin polymerization catalyst having a second comonomerincorporation index different than the first comonomer incorporationindex, and a chain shuttling agent, wherein the ethylene/α-olefininterpolymer comprises at least 50 mole percent ethylene and: (a) has atleast one molecular fraction which elutes between 40° C. and 130° C.when fractionated using TREF, characterized in that the fraction has ablock index of at least 0.5 and up to about 1; and (b) has an averageblock index greater than zero and up to about 1.0 and a molecular weightdistribution, Mw/Mn, greater than about 1.3; and (c) has a storagemodulus at 25° C., G′ (25° C.) and a storage modulus at 100° C., G′(100° C.), wherein the ratio of G′ (25° C.) to G′ (100° C.) is in therange of about to about 9:1.
 27. The composition of claim 26 wherein thenotched Izod impact strength at 20° C. is at least 5% higher as comparedto the same propylene polymer composition without the ethylene/α-olefininterpolymer.
 28. The composition of claim 26 wherein the notched Izodimpact strength at 20° C. is at least 10% higher as compared to the samepropylene polymer composition without the ethylene/α-olefininterpolymer.
 29. The composition of claim 26 wherein the notched Izodimpact strength at 20° C. is at least 15% higher as compared to the samepropylene polymer composition without the ethylene/α-olefininterpolymer.
 30. A fabricated article made from the composition ofclaim 26.